Kpk Mdcat Mock Paper 4 — Solved Past Paper with Answers

Q1. Identify the errors and choose the correct option:

• A. Guliver travels was written to Swift.
• B. Guliver travels was written at Swift.
• C. Guliver’s Travels was written by Swift.✓
• D. Gulivers’ Travel was written by Swift.

Explanation: Option A and Option B are incorrect since the apostrophe + ‘s’ (‘s) is absent which is needed after the noun “Gulliver” to indicate the possessive nature of the travels (i.e. to indicates that the travels were of Gulliver). Since Gulliver had more than one travel in the story, the word should be “Travels” and not “Travel”. Hence, Option D is incorrect, and Option C is correct.

Q2. Fill in the blank with appropriate article as required._ umbrella is of no avail against a thunderstorm.

• A. The
• B. A
• C. An✓
• D. No article required

Explanation: "An" umbrella is of no avail against a thunderstorm. The indefinite article "an" is used in this sentence because it introduces the general concept of an umbrella without specifying a particular umbrella. It implies that any umbrella in general would not be effective against a thunderstorm.

Q3. Choose the correct sentence:

• A. I wish I have been a millionaire.
• B. I wish I am being a millionaire.
• C. I wish I were a millionaire.✓
• D. I wish I was a millionaire.

Explanation: The correct sentence is:I wish I were a millionaire.The sentence is used by the speaker to express an unfulfilled desire (to be a millionaire). This means that the person is referring to an event in the past that they wanted to be trueHence, Option C is correct option.

Q4. Choose the correct option.

• A. Samar bought an apple, an orange and an pear.
• B. Samar bought an apple a orange and a pear.
• C. Samar bought an apple, an orange and a pear.✓
• D. Samar bought a apple, an orange and a pear.

Explanation: This option is correct. It correctly uses commas to separate the items in the list ("an apple", "an orange", and "a pear"), and the articles ("an" and "a") are used correctly.

Q5. He extolled the virtues of the Russian people. [The underlined word means:]

• A. Admired
• B. Praised✓
• C. Censured
• D. Adopted

Explanation: Extoll means to praise enthusiastically.Extol (verb) - highly praised; lauded or acclaimed.Present tense: Extol/ExtolsPresent participle: ExtollingPast tense: ExtolledPast participle: ExtolledExample Sentences:She is forever extolling the virtues of her children.The health benefits of exercise are widely extolled.They kept extolling my managerial skills.

Q6. His bad friends will ruin him.[Passive form of the sentence is.]

• A. He will be ruin by his bad friends.
• B. He is ruined by his bad friends.
• C. He will be ruined by his bad friends.✓
• D. He is being ruined by his bad friends.

Explanation: This highlights the correct structure of the passive voice where the subject is being affected. The correct use of tense is also employed, “will be ruined”, in accordance with the original, active sentence

Q7. The rising price of electricity has _ affected the less fortunate.

• A. Positively
• B. Not
• C. Adversely✓
• D. Slowly

Explanation: Adversely - in a negative, contrary, or unfavorable way or direction. The less fortunate could only be adversely (negatively) affected as they cannot afford to pay the increasing prices

Q8. 'Money Grubbing‘ impllies:

• A. Money saving
• B. Money making
• C. Money hunting✓
• D. Money spending

Explanation: Money-grubbing means ‘overeager to make money’."Money hunting" is not a commonly used phrase, and it does not have a standard or widely recognized meaning in the English language. It could potentially be a colloquial term or a unique expression used by a particular group or community, but without further context, it's challenging to determine its specific meaning. If "money hunting" refers to a specific concept or context, please provide more information, and I'll do my best to help you understand its meaning.

Q9. 'Get into a soup‘ impllies:

• A. Face a predicament✓
• B. Play a game of cards
• C. Swallow a fly in soup
• D. Go for hot spicy soup

Explanation: Get into a soup’ means to be in an unpleasant or difficult situation.Predicament is a difficult, unpleasant, or embarrassing situation. So option A is correct.

Q10. All of the following are co-enzymes except:

• A. NAD
• B. FAD
• C. NADP
• D. ADP✓

Explanation: Coenzymes are non-protein, organic compounds required by many enzymes for catalytic activity. They are often vitamins or derivatives of vitamins. The main function of coenzymes is to act as intermediate carriers of transferred electrons or functional groups in a reaction.ADP (adenosine diphosphate) is a biological molecule consisting of one adenine, one sugar, and two phosphates. Its most important role is that it is combined with a phosphate molecule to make ATP, the premier energy molecule in living cells. ADP is also used to help activate platelets in clotting. ADP is not a coenzyme.

Q11. Polio immunization vaccine is effective:

• A. 50%
• B. 60%
• C. 80%
• D. 90%✓

Explanation: Polio, or poliomyelitis, is a disabling and potentially deadly disease. It is caused by the poliovirus. The virus spreads from person to person and can infect a person’s spinal cord, causing paralysis. There is no cure for polio, but it can be prevented with safe and effective vaccination.Two types of vaccines protect against polio, or poliomyelitis: 1. Inactivated poliovirus vaccine (IPV) - It is given by a shot in the leg or arm, depending on the patient’s age. 2. Oral poliovirus vaccine (OPV) - Children receive doses of the vaccine by drops in the mouth.A person is considered to be fully vaccinated if they received:Four doses of any combination of IPV and trivalent oral polio vaccine (tOPV), orA primary series of at least three doses of IPV or tOPVTwo doses of inactivated polio vaccine (IPV) are 90% effective or more against polio; three doses are 99% to 100% effective.

Q12. Balantidium coli lives in the intestinal tract of:

• A. Pigs and rats
• B. Pigs and monkeys✓
• C. Rats and dogs
• D. Cats and sheep

Explanation: Swine are the primary reservoir hosts of Balantidium coli. Humans can also be reservoirs, and other potential animal hosts include non-human primates. Balantidium coli is a normal inhabitant of the cecum and colon of non-human primates and pigs.Mode of Transmission:Balantidium coli is transmitted through the fecal-oral route. Humans can become infected by eating and drinking contaminated food and water that has come into contact with infective animal or human fecal matter.Signs and Symptoms:Balantidium coli infects the large intestine in humans and produces infective microscopic cysts that are passed in the feces, potentially leading to re-infection or infection of others. Immune-compromised people are the most likely to experience more severe signs and symptoms. These include persistent diarrhea, dysentery, abdominal pain, weight loss, nausea, and vomiting. If left untreated, perforation of the colon can occur.

Q13. In stomach the pepsinogen is synthesized and secreted by:

• A. Mucus cells
• B. Parietal cells
• C. Hormonal cells
• D. Chief cells✓

Explanation: Pepsinogens are synthesized and secreted primarily by the gastric chief cells of the human stomach before being converted into the proteolytic enzyme pepsin, which is crucial for digestive processes in the stomach.

Q14. Amount of O2 carried by red blood cells is:

• A. 77%
• B. 90%
• C. 87%
• D. 97%✓

Explanation: Red blood cells (also known as erythrocytes) contain a protein called hemoglobin, which carries oxygen from the lungs to all parts of the body. Haemoglobin is an iron-containing protein that is found within all RBCs. Haemoglobin is made of four subunits: two alpha subunits and two beta subunits. Each subunit surrounds a central heme group that contains iron and binds one oxygen molecule, allowing each hemoglobin molecule to bind four oxygen molecules, forming oxyhemoglobin. Approximately, 97% of oxygen is carried by the red blood cells as oxyhemoglobin, while 3% is transported as dissolved oxygen in the plasma.

Q15. 6-NADH can yield:

• A. 12-ATP
• B. 38-ATP
• C. 18-ATP✓
• D. 36-ATP

Explanation: An NADH molecule on oxidation theoretically releases sufficient energy to make 3 ATP molecules. Therefore, 6 molecules of NADH can yield:6 NADH → 6 3 = 18 molecules of ATPThe actual yield of ATP per molecule of NADH is however less. It's 2.5 molecules of ATP/NADH. Therefore, the actual yield of ATP when 6 NADH molecules undergo oxidation is:6 NADH → 6 2.5 = 15 molecules of ATPSince 15 molecules of ATP is not given as an option, the theoretical yield of ATP i.e. 18 molecules (Option C) is the answer.

Q16. Blood pressure towards the brain during rest hours is:

• A. 850mm/minute
• B. 900mm/minute
• C. 750mm/minute✓
• D. 730mm/minute

Explanation: Cerebral circulation refers to the flow of blood through the network of blood vessels supplying the brain. The arteries deliver oxygenated blood, glucose, and other nutrients to the brain and the veins carry deoxygenated blood back to the heart, removing carbon dioxide, lactic acid, and other metabolic products. The four main arteries that supply blood to our brain are the left and right internal carotid arteries and the left and right vertebral arteries. When cerebral circulation is impaired, less oxygen and glucose reach the brain. This can cause brain damage and neurological problems. The rate of blood flow toward the brain during rest is 750ml/minute.This is a value to be memorized from the following table given in KPK Biology Book 1.

Q17. Photo-respiration can generate:

• A. 4-ATP
• B. 36-ATP
• C. 32-ATP
• D. NO-ATP✓

Explanation: Photorespiration (also known as the C2 cycle) is a metabolic process in plants where the enzyme rubisco combines O2 with RuBP in the presence of light to form unwanted products. The process leads to the production of CO2. The rate of photorespiration increases at high light intensities. At high light intensities, the rate of photolysis of water and light-dependent reactions increases. This increases the rate of production of oxygen leading to an increase in [O2] : [CO2], thereby favoring the oxygenase activity of rubisco combining O2 with RuBP. Photorespiration causes the rate of photosynthesis to decrease as less RuBP is available for carbon fixation. Thus, it leads to a decrease in the rate of the Calvin cycle and hence the overall rate of photosynthesis. It wastes energy and decreases sugar synthesis. In the photorespiratory pathway, there is no synthesis of ATP or NADPH.

Q18. Sucrose on hydrolysis gives:

• A. One mole of glucose and two moles of fructose
• B. One mole of glucose and one mole of fructose✓
• C. Two moles of glucose
• D. Two moles of fructose

Explanation: Sucrose is a disaccharide made up of two simpler sugar units. Hydrolysis breaks the glycosidic bond, yielding its constituent monosaccharides: one molecule of glucose and one molecule of fructose.

Q19. Polysaccharide cellulose is the building material of:

• A. Primary cell wall✓
• B. Secondary cell wall
• C. Middle lamella
• D. Plasma membrane

Explanation: Cellulose is a crucial polysaccharide that forms the structural component of the primary cell wall in plants. It provides tensile strength and rigidity, allowing the plant to maintain its shape. The secondary cell wall, although providing additional support, is not primarily composed of cellulose but rather lignin and other compounds. The middle lamella is mainly composed of pectin and acts as an adhesive between cells. The plasma membrane is not part of the cell wall and does not contain cellulose, as it is primarily made up of lipids and proteins.

Q20. Replication progresses at a rate of about 50 base pairs per second in:

• A. Bacteria
• B. Virus
• C. Eukaryote✓
• D. All of the above

Explanation: In eukaryotes, such as humans, DNA replication occurs at approximately 50 base pairs per second. This slower rate compared to prokaryotes is due to the complexity of eukaryotic chromosomal structures and the presence of multiple origins of replication. Bacteria replicate at a much faster rate of about 1000 nucleotides per second due to their simpler circular DNA and fewer regulatory complexities. Viruses do not have a fixed replication rate as it varies significantly depending on the virus type and the host cell machinery they exploit. Therefore, the correct answer is C: Eukaryote.

Q21. Myoglobin is found in:

• A. Bone
• B. Connective tissue
• C. Muscles✓
• D. Cartilage

Explanation: Myoglobin is a protein found in muscle fibers, responsible for storing oxygen and facilitating its availability during muscle contraction. This is crucial to meet the high oxygen demands for energy production within muscle cells. Unlike bones, connective tissue, and cartilage, muscles require direct oxygen availability for sustained activity, which is why myoglobin is present there. Bones, connective tissue, and cartilage serve structural and supportive roles and do not have the same oxygen storage needs.

Q22. Messer‘s capsules are the receptors for

• A. Temperature
• B. Pain
• C. Pressure
• D. Touch✓

Explanation: Mesissner corpuscles are an integral aspect of the human sensory system, required for discriminatory touch and grip control. Therefore the answer is D.

Q23. Human body thermostat is:

• A. Medulla
• B. Medulla oblongata
• C. Body fluid
• D. Hypothalamus✓

Explanation: The hypothalamus in the brain is the master switch that works as a thermostat to regulate the body’s core temperature. When our internal temperature changes, sensors in the central nervous system send messages to the hypothalamus. In response, it sends signals to various organs and systems in the body. They respond with a variety of mechanisms. If the body needs to cool down, the mechanisms include: sweating, and vasodilation. If the body needs to warm up, the mechanisms include vasoconstriction, thermogenesis, and hormonal thermogenesis.

Q24. How many pairs of cranial nerves are mixed in nature?

• A. 02 pairs
• B. 04 pairs✓
• C. 06 pairs
• D. 08 pairs

Explanation: The cranial nerves are a set of 12 paired nerves in the back of our brain. Cranial nerves send electrical signals between our brain, face, neck, and torso. The cranial nerves help us taste, smell, hear, and feel sensations. They also help us make facial expressions, blink our eyes and move our tongues. Mixed cranial nerves are the cranial nerves that contain sensory and motor nerve fibers. There are four such nerves in our peripheral nervous system: The trigeminal nerve (CN V), Facial nerve (CN VII), Glossopharyngeal nerve (CN IX), and Vagus nerve (CN X).

Q25. "80–S" ribosome is formed by the combination of:

• A. 30S and 40S
• B. 70S and 10S
• C. 50S and 30S
• D. 60S and 40S✓

Explanation: Ribosomes are non-membrane-bounded organelles that are present in large numbers in all living cells and serve as the site of protein synthesis. Ribosomes occur both as free particles in prokaryotic and eukaryotic cells and as particles attached to the membranes of the endoplasmic reticulum in eukaryotic cells. Each ribosome is composed of two subunits, a larger one and a smaller one, each of which has a characteristic shape. Ribosomes are the sites at which information carried in the genetic code is converted into protein molecules. 80S ribosomes are found in eukaryotic cells. 80S ribosomes contain a small 40S subunit and a large 60S subunit. The large subunit (the 60S) catalyzes the formation of the peptide bond, and the small 40S ribosomal unit holds the mRNA molecule so that tRNA can compare and attach amino acids to it.

Q26. The optimum pH of enzyme maltase is:

• A. 4.5
• B. 5.5
• C. 6.1 – 6.8✓
• D. 6.7 – 7

Explanation: Maltase is an enzyme that catalyzes the hydrolysis of the disaccharide maltose to the simple sugar glucose. The enzyme is found in plants, bacteria, and yeast; in humans and other vertebrates, it is thought to be synthesized by cells of the mucous membrane lining the intestinal wall. Optimum pH is the pH value at which an enzyme can work best. The optimum pH of maltase falls within the range of 6.1 - 6.8. Options A, B, and D are incorrect as they suggest pH values outside the actual range of maltase's optimum pH.

Q27. Deficiency of which of the following causes diuresis?

• A. LH (Luteinizing Hormone)
• B. ACTH (Adrenocorticotropic Hormone)
• C. FSH (Follicle-Stimulating Hormone)
• D. ADH (Antidiuretic Hormone)✓

Explanation: Antidiuretic hormone (ADH) is a chemical produced in the brain that causes the kidneys to release less water, decreasing the amount of urine produced. A high ADH level causes the body to produce less urine. A deficiency results in greater urine production.ADH (Antidiuretic Hormone), also known as vasopressin, is a hormone produced by the hypothalamus and released by the posterior pituitary gland. Its primary role is to regulate the water balance in the body by controlling the amount of water reabsorbed by the kidneys. ADH plays a crucial role in maintaining proper hydration and preventing excessive water loss.The main functions of ADH in the kidneys are as follows:1. Water reabsorption: When the body is dehydrated or when the blood osmolarity (concentration of solutes) increases, the hypothalamus senses this change and signals the posterior pituitary to release ADH into the bloodstream. ADH then acts on the kidney's collecting ducts, making them more permeable to water. As a result, water is reabsorbed from the filtrate back into the bloodstream, reducing the amount of water lost in the urine.2. Concentration of urine: By increasing water reabsorption, ADH helps in concentrating urine. When the body is dehydrated, ADH levels rise, and more water is reabsorbed from the urine, leading to a reduced volume of urine with a higher concentration of waste products.3. Regulation of blood pressure: In addition to its role in water balance, ADH also has vasoconstrictive effects, meaning it can constrict blood vessels. This property helps maintain blood pressure by narrowing blood vessels and increasing vascular resistance.Imbalances in ADH levels can lead to various medical conditions. For example:1. Diabetes Insipidus: In diabetes insipidus, the body either fails to produce enough ADH (central diabetes insipidus) or the kidneys do not respond appropriately to ADH (nephrogenic diabetes insipidus). As a result, excessive amounts of dilute urine are produced, leading to increased thirst and frequent urination.2. Syndrome of Inappropriate ADH (SIADH): In SIADH, the body releases excessive amounts of ADH, leading to water retention and a decreased concentration of sodium in the blood. This can result in hyponatremia (low blood sodium levels) and fluid overload.The regulation of ADH release is tightly controlled by the body's homeostatic mechanisms, ensuring that water balance is maintained within a narrow range. ADH is a critical hormone in the body's overall water balance and helps to ensure that the body remains properly hydrated and the blood osmolarity remains within a healthy range.

Q28. In which of the following is the phenotypic and genotypic ratio the same?

• A. Co-dominance
• B. Over dominance
• C. Epistasis
• D. Incomplete dominance✓

Explanation: In incomplete dominance, the heterozygous phenotype is a blend of the two homozygous phenotypes, resulting in a phenotypic ratio that matches the genotypic ratio. For instance, in snapdragons, crossing red (RR) with white (rr) results in pink (Rr) offspring, where the intermediate phenotype is directly reflective of the genotype. This differs from co-dominance, over dominance, and epistasis, where phenotypic expressions create ratios different from the genotypic ratios due to various interactions and expressions of the alleles.

Q29. Nucleus was discovered by:

• A. Waldyne
• B. T.H. Margan
• C. Robert Brown✓
• D. Kohler

Explanation: The correct answer is Robert Brown, who discovered the cell nucleus in 1831 while examining plant cells under a microscope. His observations laid foundational work for cell biology. Other options like Waldyne and Kohler are not associated with this discovery, and T.H. Margan is a misspelling of T.H. Morgan, who was unrelated to the discovery of the nucleus.

Q30. Mature ovum in human beings is surrounded by:

• A. Plasma membrane
• B. Vitelline membrane
• C. Corona radiata
• D. All of the above✓

Explanation: Mature ova (egg cells) in humans are surrounded by all three: plasma membrane, vitelline membrane, and corona radiata.

Q31. In mitochondria UGA Codon act to specify

• A. Arginine
• B. Glutamine
• C. Tryptophan✓
• D. Valine

Explanation: A codon is a sequence of three DNA or RNA nucleotides that corresponds with a specific amino acid or stop signal during protein synthesis. Tryptophan is an essential amino acid used to make proteins. The body does not make it, so it must be consumed in the diet. It is an amino acid needed for normal growth in infants and for the production and maintenance of the body's proteins, muscles, enzymes, and neurotransmitters. Tryptophan is encoded by a single codon UGG in most organisms. Since mitochondria are semi-autonomous organelles they can synthesise their proteins. Hence, tryptophan is encoded by the codon UGA in mitochondria.

Q32. The Oligosaccharides class of carbohydrates contain monosaccharides of about:

• A. 2 to 8 units
• B. 2 to 9 units
• C. 2 to 10 units✓
• D. 2 to 11 units

Explanation: Oligosaccharides are carbohydrates composed of 2 to 10 monosaccharide units. They are formed by the joining of monosaccharide units via glycosidic bonds. Oligosaccharides that contain 2 monosaccharide units are known as disaccharides. Option C is correct because it falls within the defined range for oligosaccharides. Options A, B, and D are incorrect as they either have a narrower or broader range of monosaccharide units than what is characteristic of oligosaccharides.

Q33. Chemiosmosis occurs in the:

• A. Grana
• B. Stroma
• C. Thylakoids✓
• D. Intergrana

Explanation: In chloroplasts, chemiosmosis occurs in the thylakoids.

Q34. If two heterozygous tall plants are crossed together, the proportion of phenotypically tall plants will be:

• A. 50%
• B. 25%
• C. 75%✓
• D. 100%

Explanation: A cross between two heterozygous tall plants results in 25% homozygous tall, 50% heterozygous tall, and 25% dwarf plants. So we add 50+25 to get 75% as the proportion of phenotypically tall plants.

Q35. Erepsin acts upon:

• A. Polypeptides
• B. Carbohydrates
• C. Dipeptides✓
• D. Fats

Explanation: Erepsin consists of many enzymes and works best in alkaline pH. It doesn't act upon proteins but does act upon lower peptides such as dipeptides, hence the answer will be C.

Q36. Cristea of mitochondria are the sites of:

• A. Electron transport chain✓
• B. Photophosphorylation
• C. Krebs cycle
• D. Glycolysis

Explanation: The correct answer is A, the electron transport chain, which occurs on the cristae of the mitochondria. These folds provide a large surface area for the chain's protein complexes to facilitate ATP production. Photophosphorylation (Option B) occurs in chloroplasts, not mitochondria. The Krebs cycle (Option C) takes place in the mitochondrial matrix, not the cristae. Glycolysis (Option D) occurs in the cytoplasm, outside of the mitochondria.

Q37. Biorhythms are called circadian which means about one day so they are also called?

• A. Diurnal tempo
• B. Diurnal time
• C. Diurnal rhythms✓
• D. All of these

Explanation: "Diurnal rhythms" are the circadian rhythm synced with day and night (24 hours). Biorhythms are often referred to as "diurnal rhythms" because they are biological cycles that repeat approximately every 24 hours, corresponding to the day-night cycle. Option A,B and D are incorrect.

Q38. What is the most common fuel of energy for cells?

• A. Protein
• B. Lipid
• C. Carbohydrate✓
• D. None of these

Explanation: The most common fuel of energy for cells is carbohydrate. Carbohydrates are broken down into glucose, which is then used to produce ATP, the cell's energy currency. ATP is used to power all of the cell's activities, including muscle contraction, cell division, and the transport of molecules across the cell membrane.

Q39. The bacteriophage incorporates into the host genome in which phase?

• A. Lysogenic cycle✓
• B. Lytic cycle
• C. Both
• D. None of the above

Explanation: The bacteriophage incorporates into the host genome in the lysogenic cycle. In the lysogenic cycle, the bacteriophage DNA integrates into the host DNA and becomes a prophage. The prophage is then replicated along with the host DNA and is passed on to daughter cells when the host cell divides. The prophage can remain dormant in the host cell for many generations, or it can be triggered to enter the lytic cycle and produce new phages.

Q40. A hormone that helps in growing seedless grapes.

• A. Auxins
• B. Cytokinins
• C. Ethylene
• D. Gibberellins✓

Explanation: Gibberellin is a plant hormone regulating key processes in plants; many of them are of significant agricultural importance, such as seed germination, root and shoot elongation, and flowering. Perhaps the most widespread use of gibberellin has been in grape production. The application of gibberellin is a regular practice for the culture of the ‘Thompson Seedless’ (‘Sultanina’) cultivar of grapes to increase fruit size and is also used to induce seedlessness in certain other grape varieties.

Q41. Both DNA and RNA are synthesize by the process of:

• A. Transcription✓
• B. Replication
• C. Polymerization
• D. PCR

Explanation: The process by which DNA is copied to RNA is called transcription.

Q42. The cross between two dissimilar individuals is called:

• A. Test cross
• B. Interbreeding
• C. Epistasis
• D. Hybridization✓

Explanation: Hybridization is the process of an animal or plant breeding with an individual of another species or variety. So D is the correct option.

Q43. Brunner‘s glands are found in:

• A. Stomach
• B. Duodenum✓
• C. Ileum
• D. Colon

Explanation: Brunner’s glands are branched tubular mucus glands normally found in the mucosa and submucosa of the duodenum. Therefore the answer is B.

Q44. Which viruses can convert normal cells into cancer cells?

• A. Retrovirus✓
• B. Adenovirus
• C. Poliovirus
• D. All of the above

Explanation: Retroviruses are a type of virus that can potentially convert normal cells into cancer cells. Retroviruses, like the human immunodeficiency virus (HIV), have an RNA genome that is reverse transcribed into DNA and integrated into the host cell's genome. This integration process can disrupt normal cellular genes or regulatory elements, leading to uncontrolled cell growth and potentially causing cancer.

Q45. Which one of the following is correct?

• A. Lymph = Plasma + RBC + WBC
• B. Blood = Plasma + RBC + WBC + Platelets✓
• C. Plasma = Blood – Lymphocytes
• D. Serum = Blood + Fibrinogen

Explanation: Blood is a fluid connective tissue that circulates through our body and performs various functions, including transport of oxygen, nutrients, hormones, and waste products. It consists of plasma, which is the liquid portion of blood, and formed elements, including red blood cells (RBCs), white blood cells (WBCs), and platelets.

Q46. The cardiac pacemaker in a patient fails to function normally. The doctors find that an artificial pacemaker is to be grafted in him.It is likely that it will be grafted at the site of:

• A. Atrioventricular bundle
• B. Purkinje system
• C. Sinoatrial node✓
• D. Atrioventricular node

Explanation: SA (sinoatrial) node is a specialized bundle of neurons located in the upper part of the right atrium of the heart. SA node is the natural cardiac pacemaker from which the heartbeat originates. If this system is damaged, it may send non­coordinated impulses to the heart chambers resulting in symptoms like irregular heart rate, tiredness, dizziness, and loss of consciousness. As the pacemaker cells create this rhythmical impulse therefore an artificial pacemaker is implanted at the site of the SA node to mimic the actions of the node and conducting system and helps to regulate heartbeat.

Q47. Bundle of His is a network of:

• A. Muscle fibers distributed throughout the heart walls
• B. Muscle fibers found only in the ventricle wall.✓
• C. Nerve fibers distributed in ventricles
• D. Nerve fibres found throughout the heart

Explanation: The Bundle of His is a network of the muscle fibers found in the wall of ventricles which transmits the electrical impulses from AV node to the point of the apex of heart.

Q48. Impulse of heartbeat originates from the:

• A. SA node✓
• B. AV node
• C. Vagus nerve
• D. Cardiac nerve

Explanation: The SA node (SA stands for sinoatrial) is one of the major elements in the cardiac conduction system, the system that controls the heart rate. This stunningly designed system generates electrical impulses and conducts them throughout the muscle of the heart, stimulating the heart to contract and pump blood.

Q49. Which of the following statements is true for lymph?

• A. WBC+ proteins✓
• B. Blood + RBCs and some proteins
• C. RBCs + WBCs + plasma
• D. RBCs + proteins + platelets

Explanation: Lymph contains white blood cells and proteins but no RBCs, playing a key role in immunity and fluid balance.

Q50. The difference between the pulmonary artery and the pulmonary vein is that the pulmonary artery has:

• A. No endothelium
• B. Valves
• C. Thicker walls✓
• D. Oxygenated blood

Explanation: Pulmonary arteries have thicker muscular walls to withstand higher pressure from the heart, whereas pulmonary veins have thinner walls as they return blood at lower pressure.

Q51. Arteries carry oxygenated blood except:

• A. Pulmonary✓
• B. Cardiac
• C. Hepatic
• D. Systemic

Explanation: The pulmonary artery carries the blood from the right ventricle of the heart to the lungs for oxygenation so it carries deoxygenated blood.

Q52. Removal of calcium from freshly collected blood would:

• A. Cause delayed clotting
• B. Prevent clotting✓
• C. Cause immediate clotting
• D. Prevent destruction of hemoglobin.

Explanation: The correct answer is Option B: prevent clotting. Calcium ions play a critical role in the blood clotting process by enabling the conversion of prothrombin to thrombin and fibrinogen to fibrin, which are essential steps in forming a blood clot. Therefore, if calcium is removed from blood, these reactions cannot occur, effectively preventing clot formation. Option A is incorrect because delayed clotting implies that clotting will still occur, which is not the case when calcium is removed. Option C is incorrect because calcium removal will not cause immediate clotting; it will stop clotting altogether. Option D is incorrect because calcium removal does not relate to hemoglobin destruction or preservation.

Q53. The tricuspid valve is found in between:

• A. Sinus venous and right atrium
• B. The right atrium and right ventricle✓
• C. left ventricle and left atrium
• D. left ventricle and aorta.

Explanation: The tricuspid valve is found between the right atrium and the right ventricle.

Q54. Lymph differs from blood in having:

• A. No WBCs
• B. No proteins
• C. No RBCs✓
• D. None of the above

Explanation: The lymph is a whitish fluid which is derived from the interstitial fluid that circulates throughout the lymphatic system. It contains a variety of substance like proteins, glucose, water, salts, fats and white blood cells. It does not have RBCs.

Q55. Presence of RBC in urine is

• A. Alkaptonuria
• B. Urolithiasis
• C. Hematuria✓
• D. Proteinuria

Explanation: The presence of red blood cells (RBCs) in the urine is known as hematuria. This condition can be a sign of various health issues, including urinary tract infections, kidney stones, or more serious kidney diseases. The other options refer to different conditions: Alkaptonuria involves darkening urine due to homogentisic acid, Urolithiasis refers to stone formation which can cause hematuria as a symptom but is not the term for RBC presence itself, and Proteinuria involves proteins in the urine indicating kidney issues, but not RBCs.

Q56. The figure given below shows a small part of the human lung where exchange of gases takes place. Select the option that represents the labeled part (A, B, C, or D) correctly, along with its function:

• A. Alveolar cavity - main site of exchange of respiratory gases✓
• B. Red blood cells transport CO2 mainly
• C. Arterial capillary - passes oxygen to tissues
• D. Capillary wall - decrease surface area for exchange of O2 and CO2

Explanation: Option a is correct.All options are explained below.a)Alveolar cavity - main site of exchange of respiratory gases (Correct Option):The alveolar cavity is indeed the primary site of gas exchange in the lungs. This is where oxygen is taken up by the blood from inhaled air, and carbon dioxide is released from the blood to be exhaled. The alveoli are tiny, thin-walled air sacs within the lungs, and they provide a large surface area for efficient gas exchange.B: Red blood cells transport CO2 mainly: This statement is accurate. Red blood cells (RBCs) play a crucial role in the transport of carbon dioxide (CO2). They carry CO2 from body tissues to the lungs, where it can be exhaled.C: Arterial capillary - passes oxygen to tissues: Arterial capillaries are part of the circulatory system and are responsible for delivering oxygen-rich blood to body tissues, not for "passing oxygen to tissues." Oxygen is released from the blood in the tissues and taken up by the cells. The statement does not accurately describe the function of arterial capillaries.D: Capillary wall - decrease surface area for exchange of O2 and CO2: Capillaries, including the capillary walls, serve the vital function of facilitating the exchange of oxygen and carbon dioxide between the blood and the surrounding tissues. They do not decrease the surface area for gas exchange but rather maximize it.Summary: The correct option is A, which correctly identifies the labeled part as the alveolar cavity, the primary site of gas exchange in the lungs. The other options either describe incorrect functions or are not accurate representations of the labeled structures in the diagram.

Q57. A large proportion of oxygen remains unused in the human blood even after its uptake by the body tissues. This O2 _.

• A. Acts as a reserve during muscular exercise✓
• B. Raises the pCO2 of blood to 75 mmHg
• C. Is enough to keep oxyhaemoglobin saturation at 96%
• D. Helps in releasing more O2 to the epithelial tissues

Explanation: The unused oxygen in the blood acts as a reserve, which can be utilized during physical activities such as exercise when the body's oxygen demand increases. This ensures sufficient oxygen supply to the muscles.

Q58. Which one of these is the possibility for most of us with regard to breathing, by making a conscious effort?

• A. One can consciously breathe in and out using only the diaphragm without moving the ribs✓
• B. It is possible to completely empty the lungs by forcefully exhaling all air
• C. You can exhale all air from the lungs without any residual volume
• D. Breathing out through the Eustachian tubes is possible by closing both the nose and mouth

Explanation: Conscious control can be exerted to use the diaphragm alone for breathing, a technique known as diaphragmatic breathing. This method is often employed in relaxation and meditation practices.

Q59. The bulk of carbon dioxide (CO2 ) released from body tissues into the blood is present as:

• A. Bicarbonate in blood plasma and RBCs✓
• B. Free CO2 in blood plasma
• C. 70% carbamino­haemoglobin and 30% as bicarbonate
• D. Carbamino­haemoglobin in RBCs

Explanation: Most of the carbon dioxide released from body tissues into the blood is transported as bicarbonate ions in both the plasma and red blood cells. A smaller amount binds with hemoglobin to form carbaminohemoglobin, and only a tiny fraction remains as free CO₂ in the plasma.

Q60. Listed below are four respiratory capacities (i–iv) and four jumbled respiratory volumes of a normal human adult. Which one of the following is the correct matching of two capacities and volumes?

• A. (ii) 2500 mL, (iii) 4500 mL
• B. (iii) 1200 mL, (iv) 2500 mL
• C. (iv) 3500 mL, (i) 1200 mL✓
• D. (i) 4500 mL, (ii) 3500 mL

Explanation: All options are explained below:a)(ii) 2500 mL, (iii) 4500 mL:This option pairs capacity (ii) with 2500 mL and capacity (iii) with 4500 mL. This is an incorrect match. It doesn't align with the jumbled respiratory volumes provided in the question.B. (iii) 1200 mL, (iv) 2500 mL: This option pairs capacity (iii) with 1200 mL and capacity (iv) with 2500 mL. It also accurately pairs the capacities with their respective volumes.C. (iv) 3500 mL, (i) 1200 mL (Correct Option):This option pairs capacity (iv) with 3500 mL and capacity (i) with 1200 mL. If this is the correct option, it means that capacity (i) has a volume of 1200 mL, and capacity (iv) has a volume of 3500 mL, as per the question.D. (i) 4500 mL, (ii) 3500 mL:This option pairs capacity (i) with 4500 mL and capacity (ii) with 3500 mL. This is an incorrect match and doesn't align with the jumbled respiratory volumes provided in the question.Summary: The correct match is option C, which pairs capacity (iv) with 3500 mL and capacity (i) with 1200 mL, as indicated by the jumbled respiratory volumes provided in the question. The other options provide incorrect pairings of respiratory volumes with capacities.

Q61. Which one of the following statements is incorrect?

• A. Eggs in the ovaries ripen when they meet a sperm✓
• B. Girls are born with thousands of eggs in their ovaries
• C. Hormones control the release of the egg from the ovary
• D. One egg is released from the ovary about every month

Explanation: Eggs in the ovaries are already fully developed when they are released. They do not need to meet a sperm in order to ripen. Once an egg is released from the ovary, it can be fertilized by a sperm and become a baby. If an egg is not fertilized, it will break down and results in mensturation.

Q62. People living at sea level have around 5 million RBCs per cubic millimeter of their blood, whereas those living at an altitude of 5400 meters have around 8 million. This is because at high altitude:

• A. People eat more nutritive food, therefore more RBCs are formed
• B. People get pollution­ free air to breath and more oxygen is available
• C. Atmospheric O2 level is less and hence more RBCs are needed to absorb the required amount of O2 to survive✓
• D. There is more UV radiation which enhances RBC production

Explanation: A. People eat more nutritive food, therefore more RBCs are formed:This statement is not accurate. The number of red blood cells (RBCs) is not primarily determined by dietary intake. RBC production is mainly regulated by the body's need for oxygen. While proper nutrition is essential for overall health, it does not directly lead to a significant increase in RBC count.B. People get pollution-free air to breathe and more oxygen is available:This statement is not accurate. While clean air and increased oxygen availability can have health benefits, they do not directly lead to an increase in RBC count. RBC production is primarily regulated by oxygen levels in the body, not external air quality.C. Atmospheric O2 level is less, and hence more RBCs are needed to absorb the required amount of O2 to survive (Correct Option):This statement is accurate. At high altitudes, the atmospheric oxygen level is lower due to reduced air pressure. To meet the body's oxygen requirements, more red blood cells (RBCs) are produced to enhance oxygen-carrying capacity. This adaptation allows individuals to absorb the required amount of oxygen to survive at high altitudes.D. There is more UV radiation which enhances RBC production: This statement is not accurate. While UV radiation can have some effects on the skin and vitamin D production, it does not directly enhance RBC production. RBC production, primarily regulated by the hormone erythropoietin, responds to oxygen levels in the body.Correct Option: C. Atmospheric O2 level is less, and hence more RBCs are needed to absorb the required amount of O2 to survive.Summary: The correct option is C, which accurately describes the adaptation of increased red blood cell (RBC) production at high altitudes. This adaptation is necessary to absorb the required amount of oxygen due to lower atmospheric oxygen levels at high elevations. The other options do not accurately explain the mechanism of RBC count increase at high altitudes.

Q63. Blood analysis of a patient reveals an unusually high quantity of carboxyhaemoglobin content. Which of the following conclusions is most likely to be correct? The patient has been inhaling polluted air containing unusually high content of:

• A. Oxygen
• B. Chloroform
• C. Carbon dioxide
• D. Carbon monoxide✓

Explanation: Carboxyhaemoglobin is formed when hemoglobin binds to carbon monoxide (CO), a process that occurs when polluted air containing high levels of carbon monoxide is inhaled. This can occur due to the incomplete combustion of fuels.

Q64. When CO2 concentration in blood increases breathing becomes:

• A. Shallower and slow
• B. There is no effect on breathing
• C. Slow and not deep
• D. Faster and deeper.✓

Explanation: An increase in CO concentration in the blood results in an increased rate (faster) and depth (deeper) of breathing. The body's response is to facilitate the removal of excess CO and restore blood gas levels to a more balanced state.

Q65. An average person not doing hard work requires energy per day about

• A. 2000 kcal✓
• B. 1000 kcal
• C. 750 kcal
• D. 2800 kcal.

Explanation: An average person who is not doing hard physical work requires about 2000 kilocalories of energy per day to maintain basic body functions like breathing, circulation, and normal activity.

Q66. Haemoglobin is a type of:

• A. Carbohydrate
• B. Respiratory pigment✓
• C. Vitamin
• D. Skin pigment

Explanation: Hemoglobin is a respiratory pigment, a protein in red blood cells that binds with oxygen in the lungs and transports it to tissues, facilitating oxygen and carbon dioxide exchange.

Q67. Mast cells of connective tissue contain:

• A. Vasopressin and relaxin
• B. Heparin and histamine✓
• C. Heparin and calcitonin
• D. Serotonin and melanin

Explanation: Mast cells are the large cells with densely granular cytoplasm that is found in connective tissues. Their granules contain histamine which is a vasodilator, heparin which is an anticoagulant and serotonin which acts as a mediator of inflammation and allergic reactions. Vasopressin is a hormone secreted by posterior pituitary gland. Calcitonin is a hormone secreted by thyroid gland. Melanin is a pigment produced by specialized epidermal cells called melanocytes. Relaxin is a hormone produced by the corpus luteum and placenta during the terminal stages of pregnancy.

Q68. Mast cells secrete:

• A. Haemoglobin
• B. Hippurin
• C. Myoglobin
• D. Histamine✓

Explanation: Mast cells are granulated wandering cells that are found in connective tissue. Their granules contain histamine which is a vasodilator. It causes a runny nose, sneezing and itching. It also narrows the airways in the lungs. Haemoglobin and myoglobin are the pigments present in the blood and muscles respectively.

Q69. The ciliated columnar epithelial cells in humans are known to occur in:

• A. The Eustachian tube and stomach lining
• B. The bronchioles and Fallopian tube✓
• C. The bile duct and oesophagus
• D. The Fallopian tubes and urethra

Explanation: The ciliated columnar epithelial cells in humans are present in the nasal passages, oviducts (Fallopian tubes) terminal bronchioles, ventricles of the brain and central canal of the spinal cord of the embryo. The columnar ciliated epithelium consists of columnar cells which bear cilia on the free surface.

Q70. In man and mammals air passes from outside into the lungs through:

• A. Nasal cavity, larynx, pharynx, trachea, bronchi, alveoli
• B. Nasal cavity, larynx, pharynx, trachea, bronchioles, alveoli
• C. Nasal cavity, pharynx, larynx, trachea, bronchioles, bronchi, alveoli
• D. Nasal Cavity, Pharynx, larynx trachea bronchi bronchioles alveoli✓

Explanation: Air passes from nostrils into the nasal cavity where the dust particles are trapped. From nasal cavity, the air moves into pharynx which is a short, vertical tube. It further leads into two tubes, trachea and oesophagus. Larynx is the upper part of trachea. Besides forming a part of the respiratory tract, it also serves as the voice box. Trachea is a thin walled tube that extends downward through the neck. It divides into two primary bronchi which on entering the lungs divide into fine branches called bronchioles which enter the alveoli. Exchange of gases occur in alveoli.

Q71. In which plant tissue does photosynthesis primarily occur?

• A. Mesophyll✓
• B. Epidermis
• C. Cortex
• D. Xylem

Explanation: Photosynthesis primarily occurs in the mesophyll tissue of plant leaves. The mesophyll tissue is specialized for photosynthesis and is located between the upper and lower epidermis of the leaf. It contains chloroplasts, the organelles responsible for capturing sunlight and carrying out photosynthesis. The mesophyll tissue consists of two main types: the palisade mesophyll, which is closely packed with elongated cells, and the spongy mesophyll, which has loosely arranged cells with air spaces for gas exchange.

Q72. Which one of the following gives rise to macrophages?

• A. Neutrophils
• B. Eosinophils
• C. Monocytes✓
• D. Lymphocytes

Explanation: Monocytes have a relatively longer lifespan and employ a more intensive approach to killing pathogens compared to neutrophils. They are also able to give rise to macrophages, hence it is the correct option.

Q73. The T-lymphocytes and B-lymphocytes are the major cells of the:

• A. Thymus
• B. Lymph nodes✓
• C. Adrenal glands
• D. Lymphatic vessels

Explanation: Lymph nodes house large populations of B and T lymphocytes for immune defense.

Q74. The antigen-antibody complexes formed in the body are taken up by:

• A. Phagocytes✓
• B. Lymphocytes
• C. Monocytes
• D. Leukocytes

Explanation: Phagocytes, such as neutrophils and macrophages, are crucial for the immune system's function of engulfing and digesting foreign particles, including antigen-antibody complexes. These cells are equipped to identify and internalize these complexes, aiding in their removal from the body. While lymphocytes are vital for recognizing antigens and initiating immune responses, they do not perform phagocytosis. Monocytes can differentiate into macrophages, which are phagocytic, but the term 'monocytes' itself does not directly imply phagocytic activity. Leukocytes encompass a broader category of white blood cells, not all of which are phagocytic.

Q75. Antivenom injection contains preformed antibodies while polio drops that are administered into the body contain:

• A. Gamma globulin
• B. Attenuated pathogens✓
• C. Activated pathogens
• D. Harvested antibodies

Explanation: The oral polio vaccine (OPV) is administered in the form of polio drops and typically contains weakened, live poliovirus strains. These weakened poliovirus strains are designed to be incapable of causing the disease but can stimulate the immune system to produce an immune response, including the production of antibodies. In some regions, an inactivated polio vaccine (IPV) is also used, which contains inactivated (killed) poliovirus and is typically administered as an injection.

Q76. All of the following protect the body against entrance of germs except:

• A. Mucus membrane
• B. WBCs
• C. Ciliated cells
• D. RBCs✓

Explanation: RBCs have no role in immunity. RBCs (red blood cells) do not protect the body against the entrance of germs. RBCs are responsible for carrying oxygen to the tissues and carbon dioxide away from the tissues. They cannot engulf or kill germs.

Q77. MALT constitutes about _ percent of the lymphoid tissue in the human body.

• A. 20%
• B. 70%
• C. 10%
• D. 50%✓

Explanation: Mucosa-associated lymphoid Tissue (MALT) are significant aggregation of lymphoid tissues that are seen in relation to the mucosa of the major tracts like a respiratory, alimentary canal, and urinogenital tracts. It constitutes about 50 percent of the lymphoid tissue in the human body. MALT includes various lymphoid structures like tonsils, Peyer's patches, and lymphoid follicles found in mucosal tissues,

Q78. These are the parts of lymphatic system:

• A. Lacteals✓
• B. Duodenum
• C. Villi
• D. Liver

Explanation: Lacteals are lymphatic capillaries in intestinal villi that absorb fats and transport them into the lymphatic system.

Q79. Which of the following explains the binding of inorganic components in structures found in erythrocytes?

• A. CO with organic portion of haem
• B. CO2 with NH2 group of haemoglobin
• C. O2 with Fe of haem✓
• D. H+ with COOH group of haemoglobin

Explanation: Oxygen binds to the iron (Fe) in haem groups of haemoglobin, forming oxyhaemoglobin to transport oxygen from lungs to tissues.

Q80. The type of blood cells that have a biconcave disc-like shape are:

• A. Lymphocytes
• B. Platelets
• C. Monocytes
• D. Red blood cells✓

Explanation: RBCs are biconcave, increasing surface area for oxygen transport. They are anucleate, flexible for capillary passage, and live ~120 days before breakdown and iron recycling.

Q81. Which one has the thicker walls than the others?

• A. Right atria
• B. Left atria
• C. Right ventricle
• D. Left ventricle✓

Explanation: The left ventricle has the thickest walls to generate enough force to pump oxygenated blood through the entire systemic circulation, unlike the right ventricle, which only pumps to the lungs.

Q82. Oxygenated blood is supplied to all body parts from:

• A. Right atrium
• B. Left atrium
• C. Right ventricle
• D. Left ventricle✓

Explanation: The left ventricle is the main pumping chamber of the heart, responsible for distributing oxygenated blood to the body. It receives oxygenated blood from the left atrium and pumps it through the aorta. The other options are incorrect because the right atrium and right ventricle handle deoxygenated blood, while the left atrium only transfers oxygenated blood to the left ventricle without directly supplying it to the body.

Q83. Pepsin hydrolyzes protein to yield:

• A. Acylglycerols
• B. Amino acids
• C. Peptones and polypeptide✓
• D. Dipeptides

Explanation: Pepsin breaks proteins into smaller chains like peptones and polypeptides.

Q84. The umbilical cord contains which of the following:

• A. Pluripotent stem cells
• B. Blood stem cells
• C. Cord blood stem cells✓
• D. Both Options A and B are correct

Explanation: The correct answer is cord blood stem cells. The umbilical cord contains blood stem cells, specifically referred to as cord blood stem cells, which are harvested from the cord blood. These cells are important due to their potential for use in medical treatments, such as regenerative therapies and transplants. Pluripotent stem cells, while capable of differentiating into any cell type, are generally associated with embryonic sources, not the umbilical cord. Therefore, the presence of pluripotent stem cells is not characteristic of the umbilical cord's contents, making Option A incorrect. Similarly, while blood stem cells are present, the term 'cord blood stem cells' is more specific and accurate, which is why Option C is the correct choice. Option D is incorrect because it suggests the presence of pluripotent stem cells in the umbilical cord, which is misleading.

Q85. What is the approximate diameter of a retrovirus?

• A. 150 nm
• B. 100 nm✓
• C. 200 nm
• D. 250 nm

Explanation: The diameter of retroviruses typically ranges from approximately 80 to 120 nanometers (nm). Retroviruses are a family of enveloped viruses characterized by their use of reverse transcriptase to convert their RNA genome into DNA upon entering host cells. The viral particles consist of an outer lipid envelope, viral glycoproteins, and an inner core containing the RNA genome and viral enzymes. The size of retroviruses can vary slightly depending on the specific type of retrovirus.

Q86. ----- is formed by two pairs of light chains, and one pair of heavy chains.

• A. Actin
• B. Myosin✓
• C. Myofibril
• D. Fibroin

Explanation: Myosin is a protein that plays a key role in muscle contraction. It is composed of two pairs of light chains and one pair of heavy chains. The light chains are smaller in size compared to the heavy chains. The combination of light chains and heavy chains forms the structure of myosin, which is responsible for the interaction between myosin and actin during muscle contraction.

Q87. To decrease the salt potential, the guard cells absorb:

• A. Sodium Ions
• B. Magnesium ions
• C. Potassium ions✓
• D. Calcium ions

Explanation: Influx of potassium ions decreases water potential in the guard cell so water enters the cell from surrounding cells. As a result salt potential decreases.

Q88. The oxygen carrying capacity of haemoglobin in humans when the blood is 100% oxygenated is:

• A. 19.4 ml
• B. 19.6 ml
• C. 20 ml✓
• D. 21 ml

Explanation: In 100 ml of blood, there is about 15 g of hemoglobin, which can bind approximately 20.1 ml of oxygen. This value is considered the oxygen binding capacity of blood (Cb). The correct answer is 20 ml because it reflects the typical carrying capacity when hemoglobin is fully saturated with oxygen. Options 19.4 ml and 19.6 ml are slightly lower than the actual capacity, while 21 ml exceeds the normal capacity for hemoglobin in fully oxygenated blood.

Q89. Bile is released from the gall bladder by the action of:

• A. Gastrin
• B. Cholecystokinin✓
• C. Secretin
• D. Renin

Explanation: When stimulated by the cholecystokinin (CCK), the gallbladder contracts pushing bile through the cystic duct and into the common bile duct.

Q90. A cell-wall that is composed of sugar and amino acids is called:

• A. Murein✓
• B. Chitin
• C. Lignin
• D. Pectin

Explanation: Peptidoglycan or murein is a polymer consisting of sugars and amino acids that forms a mesh-like peptidoglycan layer outside the plasma membrane of most bacteria, forming the cell wall. Hence the correct answer would be A.

Q91. Choose the true statement regarding the reaction given below2Na(g) + Cl2(g)--> 2NaCl(s)

• A. Chloride is oxidized and sodium is reduced
• B. Chlorine acts as an oxidizing agent and sodium as a reducing agent✓
• C. Chlorine acts as a reducing agent
• D. None of the above

Explanation: In the reaction 2Na(s) + Cl2(g) ⟶ 2NaCl(s), sodium (Na) is oxidized to Na+, losing electrons, and thus acts as the reducing agent. Chlorine (Cl₂) is reduced by gaining electrons to form Cl⁻, acting as the oxidizing agent. Therefore, the correct answer is Option B. Options A and C incorrectly describe the roles of chloride and chlorine, and Option D is incorrect because Option B is the accurate description of the reaction.

Q92. What are the values of principal quantum number and azimuthal quantum number for the last electron in Chlorine atom?

• A. 1.6
• B. 1.3
• C. 3.1✓
• D. 6.1

Explanation: The electronic configuration of chlorine is [Ne]3s23p5, indicating that the last electron is in the 3p subshell. The principal quantum number (n) for this electron is 3, corresponding to the third energy level. The azimuthal quantum number (l) is 1 for the p orbital. Options A, B, and D are incorrect because they do not match the quantum numbers for chlorine's last electron.

Q93. Kp = Kc (RT)△n in the equation if △n < 0 then:

• A. Kp = Kc
• B. Kp < Kc✓
• C. Kp > Kc
• D. Kp < 0

Explanation: Kp and Kc are equilibrium constants for reactions involving gases. Kp is used when partial pressures are involved, while Kc is used for molar concentrations. The relationship between them is given by the equation Kp = Kc (RT)△n, where △n is the change in moles of gases. When △n < 0, it implies that the number of moles of gaseous products is less than the number of moles of gaseous reactants, making (RT)△n a fraction. Thus, Kp < Kc. Option B is correct. Option A is valid when △n = 0, making Kp = Kc. Option C occurs when △n > 0, which makes Kp > Kc. Option D is incorrect as equilibrium constants cannot be negative.

Q94. Select meta directing group of the following?

• A. –OH
• B. –NR2
• C. –CN✓
• D. –OR

Explanation: The correct answer is –CN. The –CN group is a meta-directing group because it withdraws electron density from the benzene ring, particularly from the ortho and para positions, reducing their reactivity to electrophilic substitution. This makes the meta position relatively more reactive. Other groups like –OH, –NR2, and –OR are electron-donating groups, thus directing substitution to the ortho and para positions.

Q95. NH4OH(aq) ⇌ NH4+(aq)+ OH–(aq)Consider the above ionization, Ammonium chloride is added to the system.Select the correct statement.

• A. The equilibrium will shift to the right
• B. The equilibrium will shift to the left✓
• C. The equilibrium will remain undisturbed
• D. The equilibrium will be attained quickly

Explanation: By adding NH4Cl we are adding NH4+ ions into the equilibrium mixture and by doing this we are disturbing it according to Le-Chatellier's principle: the system will go in the direction to retain the equilibrium position that's why it will move to the left when conc. of products is disturbed.

Q96. Select molecule that doesn’t have unpaired electrons in anti-bonding molecular orbital’s:

• A. N2-
• B. Cl2-
• C. H2+✓
• D. O2

Explanation: To determine if a molecule has unpaired electrons in antibonding molecular orbitals, examine the molecular orbital diagrams. In H2+, the antibonding σ orbital contains a single unpaired electron, making it the correct choice. In contrast, N2-, Cl2-, and O2 all have antibonding orbitals with paired electrons, resulting in no unpaired electrons in these molecules.

Q97. The order of reducing power of halide ion is:

• A. I–1> Br–>Cl–> F–✓
• B. F–>Cl–> Br–> l–
• C. l–1>Cl–> F–> Br–
• D. Br–>Cl–> l–> F–

Explanation: From the reduction potential values, it can be seen that iodide is the best-reducing agent. It has a low reduction potential value which indicates that it easily reduces others and itself gets oxidized.

Q98. Stable electronic configuration of Cu(29) is:

• A. [Ar] 4S2 3d4
• B. [Ar] 4S0 3d10
• C. [Ar] 4S1 3d10✓
• D. [Ar] 4S2 3d7 4p2

Explanation: It is a transition element. Copper (Cu) is a chemical element, a reddish, extremely ductile metal of Group 11 (IB) of the periodic table that is an unusually good conductor of electricity and heat. Due to the interelectronic repulsions one electron present in 4s enters to 3d subshell. We can write a stable electronic configuration of copper is written as 1s22s22p63s23p63d104s1. There is additional stability because of the completely occupied 3d subshell and half-filled 4s subshell.orThe electronic configurations of copper (and chromium) are unique since without filling the 4s orbitals, electrons entered into 3-d orbitals. Copper has an atomic number of 29 hence 29 electrons are fulfilled by option C as well.

Q99. N2 + 3H2 → 2NH3In the above reaction, the limiting reagent is:

• A. N2
• B. H2✓
• C. Ammonia
• D. None of the above

Explanation: The balanced equation is shown below. N2 (g)+ 3H2 (g) → 2NH3 (g) If equal moles of each reactant are used, hydrogen will be the limiting reagent as 3 moles are hydrogen are used up for every one mole of nitrogen to form ammonia.

Q100. Hydrolysis of ester in the presence of KOH is called:

• A. Esterification
• B. Decarboxylation
• C. Saponification✓
• D. Neutralization

Explanation: Esters can be hydrolyzed to form a carboxylate salt and alcohol using KOH and water. KOH is an alkaline reagent, and the alkaline hydrolysis of esters is called saponification.

Q101. Salts which dissolve in water with evolution of heat. The effect of temperature on their solubility will be:

• A. Increases with increase in temperature
• B. Decreases with increase in temperature✓
• C. Solubility does not change
• D. In some cases it increases while in others it decreases

Explanation: In exothermic reactions, heat energy is released when the solute dissolves in a solution. Increasing temperature introduces more heat into the system. Following Le Chatelier’s Principle, the system will adjust to this excess heat energy by inhibiting the dissolution reaction. Increasing temperature, therefore, decreases the solubility of the solute. An example of a solute that decreases in solubility with increasing temperature is calcium hydroxide, which can be used to treat chemical burns and as an antacid.

Q102. The rate law equation for a reaction is given as dx/dt= K[FeCl3][KI]2. The reaction is:

• A. First order
• B. Second order
• C. Third order✓
• D. Pseudo first order

Explanation: Order with respect to FeCl₃ = 1Order with respect to KI = 2Overall order = 1 + 2 = 3

Q103. Which statement correctly describes a nucleon?

• A. Any atomic nucleus
• B. A radioactive atomic nucleus
• C. A neutron or a proton✓
• D. A neutron proton or an electron

Explanation: A nucleon is either a proton or a neutron, which are the subatomic particles found in the nucleus of an atom. They are held together by the strong nuclear force, which overcomes the repulsive forces between the positively charged protons. This binding is crucial for the stability and mass of the atom. The other options are incorrect: 'Any atomic nucleus' describes a region, not the specific particles; 'A radioactive atomic nucleus' refers to the behavior of the nucleus, not the definition of nucleons; and 'A neutron proton or an electron' includes an electron, which is not part of the nucleus.

Q104. The van der waals equation of state for no-ideal gases differs from the ideal gas law in that it accounts for:I) The mass of each molecule of the gas.II) The volume of each molecule of the gas.III) The attractive forces between molecules of the gas

• A. I, II, and III
• B. I and II only
• C. I and III only
• D. II and III only✓

Explanation: More significantly, the Van der Waals equation takes into consideration the molecular size and molecular interaction forces (attractive and repulsive forces). Sometimes, it is also referred as the Van der Waals equation of state.

Q105. The statement that heat cannot spontaneously flow from a colder to a hotter body is a result of:

• A. Henry's law
• B. The first law of thermodynamics
• C. The second law of thermodynamics✓
• D. The third law of thermodynamics

Explanation: 2nd law of thermodynamics expresses a fundamental and simple truth about the universe, it states that heat cannot flow from colder body to hotter body.

Q106. Ruther ford‘s scattering experiment demonstrates:

• A. The existence of X-rays
• B. The existence of negative particles
• C. The mass to charge ratio of the electron
• D. The nuclear model of the atom✓

Explanation: Rutherford's gold foil experiment was a pivotal moment in atomic physics. It demonstrated that the atom consists of a tiny, dense nucleus containing most of its mass, which caused the deflection of some alpha particles. This experiment refuted the plum pudding model and led to the nuclear model of the atom, where electrons orbit a central nucleus. The other options are incorrect because they relate to different discoveries: X-rays were discovered by Roentgen, J.J. Thomson demonstrated the existence of electrons, and he also found the mass to charge ratio of the electron.

Q107. Which is an incorrect statement?

• A. The ionic bonds are non-directional in character
• B. The crystals of covalent compounds are made up of molecules
• C. The covalent bonds are rigid and non-directional✓
• D. Ionic compounds have high melting points and boiling points

Explanation: Covalent bonds are directional because they involve specific orientations of shared electron pairs, leading to definite molecular shapes. This makes Option C, which claims covalent bonds are non-directional, incorrect. Option A is correct since ionic bonds are non-directional due to uniform electrostatic forces. Option B is correct as covalent compounds are indeed made of molecules. Option D is correct because ionic compounds have high melting and boiling points due to strong ionic attractions.

Q108. The heat of combustion of hydrocarbon is very useful source of heat and power, considering the combustion reaction given below. CH4(g) +O2(g) →CO2(o) + 2H2O △H for the reaction is:

• A. △H = 213 kcal/mole✓
• B. △H = 231 kcal/mole
• C. △H = 426 kcal/mole
• D. △H = 312 kcal/mole

Explanation: The enthalpy of combustion of methane (CH4) is -890 kJ/mol. To convert this to kilocalories, use the conversion factor 1 kJ = 0.239 kcal. Therefore, -890 kJ/mol × 0.239 kcal/kJ = -212.715 kcal/mol, which rounds to approximately -213 kcal/mol. This makes Option A correct. The other options provide values that are not consistent with this conversion and the known enthalpy of combustion for methane.

Q109. Vinyl acetate monomer is prepared by the reaction of acetaldehyde and acetic-anhydride. The catalyst employed is:

• A. FeCl3✓
• B. Al2O3
• C. V2O5
• D. Cr2O3

Explanation: The industrial synthesis of vinyl acetate involves the reaction of ethylene, acetic acid, and oxygen over a palladium catalyst. Palladium(II) chloride is a key component of the catalyst system for this reaction.

Q110. The atomic number of scandium is 21. What is its ground state electronic configuration?

• A. 1s22s22p63s23p63d3
• B. 1s22s22p63s23p63d14s2✓
• C. 1s22s22p63s23p63d34s2
• D. 1s22s22p63s23p63d34p1

Explanation: The electronic configuration of an atom is determined by the Aufbau Principle, which states that electrons fill the lowest energy orbitals first. For scandium, with an atomic number of 21, the correct ground state configuration is 1s22s22p63s23p63d14s2. This configuration fills the 4s orbital before starting to fill the 3d orbital, in accordance with the energy order of orbitals. The other options incorrectly fill the orbitals or suggest an incorrect order of electron filling, which does not represent the lowest energy, most stable configuration.

Q111. Shown below are portion of orbital diagrams representing the ground state electronic configuration of certain elements. Which of them obeys the Pauli‘s exclusion principle and Hund‘s rules?

• A. Option A
• B. Option B
• C. Option C
• D. Both option B and C are correct✓

Explanation: Options A and D are incorrect because two electrons with the same spin are not added to the same orbitals.

Q112. The osmotic pressure of dilute solution is given below by relationship:

• A. π = iCRT
• B. π = RCT/M✓
• C. π = nRT/V
• D. π = PV = nRT

Explanation: The correct relationship for the osmotic pressure of a dilute solution is given by the equation π = RCT/M. This equation shows that osmotic pressure is directly proportional to the temperature (T) and molar concentration (C) of the solute, and inversely proportional to the molar mass (M). The formula accounts for the behavior of the solution as it approaches ideal conditions, where R is the ideal gas constant.Option A is incorrect because it includes the van 't Hoff factor, which is not needed for non-electrolyte dilute solutions. Options C and D are incorrect as they refer to the ideal gas law, which is not applicable for calculating osmotic pressure in solutions.

Q113. Choose the one which is not an assumption of collision theory of reaction rate:

• A. For chemical reaction to occur molecule / particles must collide
• B. For reacting molecules / particles must possess a certain minimum amount of energy, the activation of energy
• C. Every collision is not productive✓
• D. For hydrogen molecule formation from atoms require specific orientation

Explanation: Actually, collision theory assumes:Only a fraction of collisions are effective, due to orientation and energy requirements.If interpreted literally as “every collision is unproductive,” it contradicts collision theory, because some collisions are productive.

Q114. A neutron with K.E equal to 0.04ev is called?

• A. Slow neutron✓
• B. Thermal neutron
• C. Fast neutron
• D. Both (a) and (b)

Explanation: Neutrons are categorized based on their kinetic energy. A slow neutron has kinetic energy below about 1 eV, which includes 0.04 eV, thereby classifying it as a slow neutron. Thermal neutrons specifically have an energy of about 0.025 eV, often in thermal equilibrium at room temperature, which does not match 0.04 eV. Fast neutrons, on the other hand, have much higher energies in the range of a few MeV, making them far more energetic than 0.04 eV. Hence, the correct answer is Option A: Slow neutron.

Q115. Radiation damages living organism is primarily due to:

• A. Excitation phenomena
• B. Ionization
• C. Photoelectric effect
• D. Heating
• E. All of them✓

Explanation: The correct answer is All of them.Radiation can harm living organisms through a combination of mechanisms: excitation can cause energy release that damages cellular structures, ionization creates reactive ions that can disrupt DNA and proteins, the photoelectric effect results in electron ejection that compromises molecular integrity, and heating can denature proteins.While each mechanism individually can cause harm, their combined effects often lead to more severe damage. The extent of damage depends on factors like radiation type and dose. Each incorrect option describes a real mechanism of radiation damage, but on their own, they do not encompass the full scope of radiation's impact on biological organisms.

Q116. Pka values of some acids are given below:Choose the weaker acid?

• A. HClO4 (–10)
• B. HBr (–9)
• C. H2SO4 (–3)✓
• D. HCl (–7)

Explanation: The strength of an acid is inversely related to its pKa value: the lower the pKa, the stronger the acid. In this question, we are looking for the acid with the highest pKa value, indicating weaker acidic strength. Among the given options, H2SO4 has a pKa of -3, which is higher than the pKa values of the other acids provided (all of which are more negative). This makes it the weakest acid in this list, although it is still generally considered a strong acid in broader terms. HClO4, HBr, and HCl all have lower pKa values, making them stronger acids.

Q117. Choose the correct order of reactivity of alkyl halides?

• A. R – I > R – Br > R – Cl > R – F✓
• B. R – Br > R – I > R – F > R – Cl
• C. R – F > R – Cl > R – Br > R – I
• D. R – Cl > R – I > R – Br > R – F

Explanation: Alkyl halides reactivity is influenced by the bond strength between the carbon (C) and halogen (X) atoms. As you move down the halogen group on the periodic table, the bond strength decreases due to the increased size and lower bond energy of the halogens. Thus, the reactivity order is R – I > R – Br > R – Cl > R – F. Iodine, being the largest halogen, forms the weakest bond with carbon, making iodo compounds the most reactive. Conversely, fluorine forms the strongest bond, making it the least reactive. The other options are incorrect because they do not correctly account for the bond strength and size of the halogens, leading to an incorrect order of reactivity.

Q118. Semi-conductor materials have:

• A. Ionic bond
• B. Covalent bond✓
• C. Mutual bond
• D. Metallic bond

Explanation: A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding. Semiconductor materials have covalent bonding between atoms (FACT). They are only able to conduct electricity due to delocalized electrons.

Q119. Select ligand which is bidentate and can form chelates:

• A. CH3 NH2
• B. PH3
• C. H2O
• D. CH2(NH2)CH2(NH2)✓

Explanation: Ethylene diamine is a bidentate ligand as it has two Nitrogens, each containing a lone pair of electrons that they can donate to form two dative bonds with one central metal atom. A, B, and C all have only one lone pair of electrons thus they are monodentate ligands.

Q120. The proton acceptor is:

• A. NH3✓
• B. BF3
• C. HCl
• D. H+

Explanation: According to the Bronsted-Lowry theory, a base is a substance that accepts protons. NH3 is a classic example of a weak base that acts as a proton acceptor. In water, it reacts to form NH4+ and OH- ions, demonstrating its ability to accept a proton. In contrast, BF3 is a Lewis acid that accepts electron pairs, not protons. HCl is a proton donor, releasing H+ ions in water, and is therefore classified as an acid. Lastly, H+ is already a proton, so it cannot act as a proton acceptor.

Q121. Choose the correct Statement:

• A. The most direct and accurate method for determining atomic masses uses mass spectrometry.
• B. An indirect but precise method for determining molecular masses is through mass spectrometry.
• C. Collision between electrons and atoms produces negative ions by the absorption of electrons by atoms or molecules.✓
• D. The first significant application of mass spectrometry was demonstrating the detection of isotopes of Argon.

Explanation: Electron Collision. Often, electron collisions with gas molecules result in electron attachment to the molecule, which forms a negative ion.

Q122. The partition coefficients of Iodine distribution between two immiscible liquids, water and carbon (tetrachloride) is given below:Choose the correct statement about the system:

• A. Iodine is extracted from CCl4 layer by water
• B. Iodine is extracted from aqueous layer by CCl4✓
• C. Iodine is more soluble in water than CCl4
• D. The value of K depends on the amount of Iodine added

Explanation: Iodine vastly prefers to dissolve in CCl4 , thus it migrates from the aqueous (H2O) phase into the non-aqueous (CCl4) phase , thus we say that CCl4 extracts the iodine from the aqueous phase.

Q123. During a experiment, one measured the mass of a mosquito and found it to be 1.20 × 10–5 Kg. The numbers of significant figures in this case are:

• A. Five
• B. One
• C. Two
• D. Three✓

Explanation: All non zero digits are significant figures and in this case there are 3 significant or non zero digits hence option D is the right choice.

Q124. Which one is a polymer substance?

• A. Glass
• B. Iron
• C. Plastic✓
• D. copper

Explanation: A polymer is a substance made of many repeating units called monomers. Plastics are formed by many identical repeating monomers thus are polymers.

Q125. Chemical shift in NMR spectroscopy is expressed as delta (δ) or tan (t) scale. Choose the correct relationship between δ and t:

• A. δ = 10 – t✓
• B. δ = 10 + t
• C. t = δ – 10
• D. t = 10 – δ

Explanation: In NMR spectroscopy, δ (delta) represents the chemical shift, while t is another scale used to express the same concept. The correct relationship between these two scales is δ = 10 – t. This means that to convert from the t scale to the δ scale, you subtract the tan value from 10. The other options are incorrect because they either add instead of subtract, reverse the roles of δ and t, or suggest a subtraction that doesn't reflect the true relationship.

Q126. Choose the correct statement:DDT an insecticide is considered as:

• A. Very unstable molecule having a half-life of 1⁄2 to 1 year
• B. Unstable molecule having a half-life of 2 to 5 years
• C. Stable molecule having a half-life of 5 to 8 years
• D. Very stable molecule having a half-life of 10 to 15 years✓

Explanation: The correct answer is Option D: 'Very stable molecule having a half-life of 10 to 15 years.' DDT (Dichlorodiphenyltrichloroethane) is a highly stable pesticide with a long environmental half-life, often cited between 2 and 15 years. This persistence is a significant reason for its controversial use and eventual ban in many countries due to environmental and health concerns. The other options underestimate DDT's stability and half-life, making them incorrect.

Q127. Waxes are the esters of fatty acids with high molecular weight.

• A. Monohydroxy alcohols✓
• B. Dihydroxy alcohols
• C. Trihydroxy alcohol
• D. All of the above

Explanation: Waxes are esters formed from the reaction of fatty acids with long-chain monohydroxy alcohols, which have one hydroxyl group. This singular hydroxyl group allows them to form ester bonds with fatty acids, producing waxes. Dihydroxy and trihydroxy alcohols contain multiple hydroxyl groups and are not typically used in wax formation. Therefore, the correct answer is monohydroxy alcohols, as they are the ones involved in the creation of waxes.

Q128. Excess of ethanol is heated with conc: sulphuric acid keeping the temperature 140°C. The product formed is

• A. C2H5OC2H5 + H2O✓
• B. C2 H4
• C. C2 H5 OH
• D. C2 H6

Explanation: At 140°C in the presence of sulfuric acid two molecules of ethanol are dehydrated (lose a molecule of water) to form ether. The sulphuric acid is regenerated and reused. Above about 160°C (320°F) ethene is produced instead, by loss of water from just one molecule of ethanol. The reaction is the following:C2H5OH + H2SO4 —> C2H5-O-C2H5 + H2O

Q129. Which one of the following acids has a strong conjugate base?

• A. CH3COOH✓
• B. HCl
• C. HNO3
• D. H2SO4

Explanation: The strength of a conjugate base is inversely related to the strength of its corresponding acid. Weak acids, like CH3COOH, have strong conjugate bases (CH3COO-, acetate ion) because they do not fully dissociate, allowing the base to effectively accept protons. In contrast, strong acids such as HCl, HNO3, and H2SO4 completely dissociate in solution, resulting in very weak conjugate bases (Cl-, NO3-, HSO4-, respectively).

Q130. In P type substances, the charge carriers in minorities are:

• A. Holes
• B. Electrons✓
• C. Protons
• D. Positive ions

Explanation: Minority charge carriers are those charge-carrying units in a substance that are very few in quantity. In p-type semiconductors, a very small number of free electrons is present. Hence, electrons are the minority charge carriers in the p-type semiconductor. In P-type semiconductors, holes are the majority charge carriers and electrons are the minority charge carriers.

Q131. All of the following are micronutrients except:

• A. Iron
• B. Copper
• C. Zinc
• D. Magnesium✓

Explanation: Magnesium (Mg2+) is an essential macronutrient of living cells and is the second most prevalent free divalent cation in plants. Mg2+ plays a role in several physiological processes that support plant growth and development.

Q132. What is true about modern methods used in the determination of the structure of compounds?

• A. Accurate but more time consuming
• B. Accurate, rapid but chemicals are used in large amounts
• C. Accurate, rapid but sophisticated and complicated
• D. Accurate, simple and less time consuming✓

Explanation: The modern methods used by scientists to identify and differentiate between cell structures are efficient, accurate, simple, and less time-consuming in comparison to the methods used in the past. Examples are IR spectroscopy, mass spectroscopy, NMR, etc.

Q133. Which is the correct statement?

• A. The average kinetic energy of the molecules depends on the volume in which the gas is enclosed.
• B. The average kinetic energy of the molecules in the gaseous state is proportional to the pressure.
• C. The average kinetic energy of the molecules in the gaseous state is proportional to the temperature.✓
• D. All of the above

Explanation: Kinetic energy is the energy a substance has because of its molecules being in motion, as a substance absorbs heat its molecules move faster, thereby increasing the substance's kinetic energy.

Q134. Hydrogen bonding do not exist in the molecule of:

• A. Hydrogen gas (H2)✓
• B. Proteins
• C. Carbohydrates
• D. Ammonia (NH3)

Explanation: Hydrogen bonding is an intermolecular force that occurs when a hydrogen atom is covalently bonded to a highly electronegative atom, such as nitrogen, oxygen, or fluorine. This interaction is absent in hydrogen gas (H2) because it consists of two hydrogen atoms bonded together, without the presence of any electronegative atoms. In contrast, proteins, carbohydrates, and ammonia all have structures that allow for hydrogen bonding due to the presence of nitrogen, oxygen, or hydroxyl groups.

Q135. Which statement is incorrect about ionization energy?

• A. Ionization energy depends upon the magnitude of nuclear charge
• B. Ionization energy depends upon the atomic radius
• C. Ionization energy depends upon the shielding effect
• D. Ionization energy does not depend upon the penetration effect of the inner orbital✓

Explanation: Option D is the correct answer because it incorrectly states that ionization energy does not depend on the penetration effect. In reality, the penetration effect allows inner orbital electrons to be closer to the nucleus, increasing the effective nuclear charge experienced by the outer electrons, and thus increasing ionization energy.Options A, B, and C correctly state the factors affecting ionization energy: nuclear charge, atomic radius, and shielding effect, respectively. Increased nuclear charge strengthens the attraction between electrons and the nucleus, raising ionization energy. A larger atomic radius weakens this attraction, lowering ionization energy. The shielding effect decreases the effective nuclear charge felt by outer electrons, also reducing ionization energy.

Q136. Can we see magnetic flux lines?

• A. Yes
• B. No✓
• C. Depends on strength of field
• D. Only when the field is large

Explanation: Magnetic flux lines are imaginary lines drawn solely for a better understanding of magnetic flux.

Q137. Spectral lines is like a _ of absorbed or emission energy in a spectrum

• A. Charged pattern
• B. Fingerprint pattern✓
• C. Discharged pattern
• D. None of these

Explanation: Fingerprints are unique to each individual, making them excellent for identification. Similarly, spectral lines serve as unique identifiers for elements. Each element has a specific set of spectral lines that act like a 'fingerprint,' allowing scientists to determine the composition of stars and galaxies. Other options, such as 'charged pattern' and 'discharged pattern,' fail to capture the critical aspect of spectral lines being distinct and identifiable for different elements.

Q138. Which among the following phenomenon shows particle nature of light?

• A. Photoelectric effect✓
• B. Interference
• C. Polarization
• D. Matter waves

Explanation: The photoelectric effect occurs when light ejects electrons from a metal surface, which can only be explained if light consists of particles (photons) with discrete energy packets. This confirms the particle nature of light as explained by Einstein's photon theory.

Q139. For ideal step up transformer Ps_Pp.

• A. Equal to✓
• B. Greater than
• C. Less than
• D. None of these

Explanation: Correct. In an ideal step-up transformer, there is no power loss, meaning the power input (Pp) equals the power output (Ps). This follows from the law of energy conservation, which states that energy cannot be created or destroyed.

Q140. The resistance of a conductor at absolute zero (0K) is:

• A. Almost zero✓
• B. Almost infinite
• C. No prediction at all
• D. May increase or decrease

Explanation: The resistance of a conductor at absolute zero (0K) is almost zero. This phenomenon is known as zero or near-zero resistance, and it occurs in materials with special properties called superconductors.Superconductors are materials that exhibit zero electrical resistance below a critical temperature. At temperatures close to absolute zero, the thermal energy becomes extremely low, and the probability of electron-impurity or electron-phonon scattering is greatly reduced. As a result, the resistance of the superconductor diminishes significantly, approaching zero.

Q141. If a system changes from a state P1V1 to P2V2 by two paths then the quantity which remains unchanged is _.

• A. dQ
• B. dW
• C. dQ-dW✓
• D. dQ+dW

Explanation: The quantity that remains unchanged is known as a state function, which depends only on the initial and final states of the system and is independent of the path taken between those states. The only state function among the given options is dQ - dW.dQ is the heat added to the system, and dW is the work done on the system. The first law of thermodynamics states that the change in internal energy of a system is equal to the heat added to the system minus the work done on the system, i.e., ΔU = dQ - dW. Thus, the quantity dQ - dW is equal to the change in internal energy, which is a state function.

Q142. The radiations all around us are called _ radiations.

• A. Natural
• B. Artificial
• C. Both A or B✓
• D. No radiation is around us

Explanation: Humans come into contact with radiation on a daily basis. These radiations are both natural, such as the rays from the sun, and artificial, such as those from our TV screens or kitchen stoves. This radiation that we experience on a daily basis is known as background radiation

Q143. An electron has charge-e- and mass m. A proton has charge e and mass 1840m. A "Proton volt" is equal to:

• A. 1 eV✓
• B. 1840 eV
• C. (1/1840) eV
• D. √1840 eV

Explanation: An electron volt (eV) is the amount of energy gained or lost by an electron when it moves through a potential difference of 1 volt. It is given by:eV=e×1VSince a proton has the same magnitude of charge as an electron (but opposite in sign), when it moves through 1 volt of potential difference, it also gains or loses the same amount of energy, i.e., 1 eV. Thus, a "proton volt" is numerically equal to one electron volt (1 eV) because energy depends on charge and potential, not on mass.

Q144. The rotational inertia of a disk about its axis is 0.70 Kg. m2. When a 2.0-kg weight is added to its rim, 0.40m from the axis, the rotational inertia becomes:

• A. 0.38 kg – m2
• B. 0.54 kg – m2
• C. 0.86 kg – m2
• D. 1.02 kg – m2✓

Explanation: The correct answer is 1.02 kg – m2. The initial rotational inertia of the disk is 0.70 kg m2. When a 2.0 kg mass is added at a radius of 0.40 m, the additional moment of inertia is calculated using Im = m × r2. Substituting the values gives Im = 2.0 kg × (0.40 m)2 = 0.32 kg m2. Adding this to the original inertia results in a total of 1.02 kg m2. The other options underestimate the impact of the added mass, leading to incorrect calculations of the total rotational inertia.

Q145. Which of the following is closest to a yard:

• A. 0.01 m
• B. 0.1 m
• C. 1 m✓
• D. 100 m

Explanation: The correct answer is 1 meter because a yard is approximately 0.9144 meters, making 1 meter the closest option. A yard is a unit of length used in the imperial system, and when converted to the metric system, it measures just under one meter. The other options are either too small (0.01 m and 0.1 m) or too large (100 m) to be considered close to a yard.

Q146. A wheel starts from rest and has an angular acceleration of 4.0 rad/s2. When it has made 10 rev its angular velocity is:

• A. 16 rad/s
• B. 22 rad/s✓
• C. 32 rad/s
• D. 250 rad/s

Explanation: To find the final angular velocity ωf, use the rotational kinematics equation: ωf = ωi + 2aθ. Given that the initial angular velocity ωi is 0 rad/s (since the wheel starts from rest), a is 4 rad/s2, and the angular displacement θ is 62.83 rad (10 revolutions), we calculate:ωf = 0 + √(2 * 4 * 62.83) = 22.41 rad/s.Thus, the correct answer is 22 rad/s.Options A, C, and D are incorrect because they result from incorrect applications of the formula or assumptions, leading to miscalculations.

Q147. In a vibrating cord the point where the particles are stationary is called:

• A. Crest
• B. Anti-node
• C. Node✓
• D. Trough

Explanation: A node is a point along a standing wave where the wave has minimum amplitude. All the particles of the string execute SHM except nodes.

Q148. When lead, 81Pb214, emits a ß- particle, the resultant nucleus will be:

• A. 83Bi214
• B. 84Po214
• C. 82Pb214✓
• D. 41TI214

Explanation: In beta decay, a neutron in the nucleus is transformed into a proton and a beta particle (an electron) is emitted. This results in an increase in the atomic number by 1 while the mass number remains unchanged. Thus, when lead, 81Pb214, emits a beta particle, it transforms into 82Pb214. The other options are incorrect as they either show an incorrect change in atomic number or involve elements that do not result from beta decay of lead.

Q149. Three equivalent resistors connected in parallel have equivalent resistance R/3. When they are connected in series then the equivalent resistance is:

• A. 3R✓
• B. R/3
• C. R
• D. 2R

Explanation: When three equivalent resistors are connected in parallel, the equivalent resistance is 3/R. When these same resistors are connected in series, their resistances add up, resulting in an equivalent resistance of 3R. Therefore, the correct option is 3R. Options B, C, and D are incorrect because they do not align with the calculations for equivalent resistance in parallel and series resistor connections.

Q150. Ohm‘s law is valid only for

• A. Thermistor
• B. Bulb filament
• C. Metals✓
• D. Semiconductors

Explanation: Ohm's law is valid for metallic conductors because they have a linear relationship between current and voltage. This makes Option C, 'Metals', the correct answer. Thermistors, bulb filaments, and semiconductors do not follow this linear relationship and hence Ohm's law is not valid for them.

Q151. Which of the given formulae would be used to calculate the wavelength of an electron? Given its velocity(v), its mass (m) and constant h:

• A. v = f.λ
• B. λ = h / mv✓
• C. s = d/t
• D. p = λ x h

Explanation: The correct formula to calculate the wavelength of an electron is λ = h / mv, known as De Broglie's wave equation. This equation takes into account Planck's constant (h), the mass of the electron (m), and its velocity (v). Option B is correct because it correctly represents this calculation. Options A, C, and D are incorrect as they represent formulas for velocity, speed, and momentum, respectively, not wavelength.

Q152. The energy stored in a charged capacltor is given by:

• A. 1/2 CV2
• B. 1/2 QV
• C. 1/2 m v2
• D. Both A and B✓

Explanation: The correct answer is Option D: Both A and B. The energy stored in a charged capacitor can be represented by the formulas E = 1/2 CV² or E = 1/2 QV. Option A and B both correctly represent the energy stored in a charged capacitor. Option C is incorrect as 1/2 mv² is the formula for kinetic energy, not the energy stored in a capacitor.

Q153. The potential difference between a pair of similar and parallel conducting plates is known. What additional information is needed in order to find the electric field strength between the plates?

• A. Separation of the plates✓
• B. Separation and area of the plates
• C. Permittivity of the medium; separation of the plates
• D. Permittivity of the medium; separation and area of the plates

Explanation: The correct answer is Option A: Separation of the plates. The electric field strength between parallel conducting plates can be calculated using the formula E = V/d, where V is the potential difference and d is the distance between the plates. Therefore, knowing the separation of the plates is the additional information needed to determine the electric field strength in this scenario.Options B, C, and D include unnecessary information such as the area of the plates and permittivity of the medium, which are not directly required to find the electric field strength between the plates.

Q154. A capacitor which has a capacitance of 1 farad (F) will:

• A. Be fully charged in 1 second by a current of 1 Ampere
• B. Store 1 coulomb of charge at potential difference of 1 volt✓
• C. Gain 1 joule of energy when 1 coulomb of charge is stored on it
• D. Discharge in 1 second when connected across a resistor of resistance 3 ohms

Explanation: A capacitance of 1F produces 1V of potential difference for an electric charge of one coulomb (1C). This statement also fully agrees with the formula C=Q/V.

Q155. The internal energy of a fixed case of an ideal gas depends on:

• A. Pressure, but not volume or temperature
• B. Temperature, but not pressure or volume✓
• C. Volume, but not pressure or temperature
• D. Pressure and temperature, but not volume

Explanation: In an ideal gas the inter-molecular collisions are assumed to be absent and the collisions are perfectly elastic, thus, the gas only possesses kinetic energy and hence the internal energy of the ideal gas only depends on temperature,hence the answer will be B.

Q156. Radioactive activity is affected by:

• A. Temperature
• B. Pressure
• C. Humidity level
• D. None of the above✓

Explanation: Radioactive decay is the process by which an unstable atomic nucleus loses energy by emitting radiation. This process is governed by nuclear forces and is not influenced by external environmental factors such as temperature, pressure, or humidity. Therefore, the correct answer is None of the above. The other options are incorrect because they suggest that external conditions, which affect chemical reactions, also affect nuclear reactions, which they do not.

Q157. The change in enthalpy at constant pressure, △H is equal to:

• A. △H = q + P△V✓
• B. △H = △E- P△V
• C. △H = △E + P△V
• D. △H = q - P△V

Explanation: The change in enthalpy, ∆H, at constant pressure is equal to the sum of the heat absorbed or released, q, and the pressure-volume work, P∆V, done on or by the system during the process. This is because enthapy, H, is defined as the sum of internal energy, U, and the product of pressure and volume, PV, and at constant pressure, the change in enthalpy is equal to the heat transferred plus the Workdone.∆H = q + P∆V

Q158. An organ pipe of length T has one end closed but the other end open. What is the wavelength of the fundamental node emitted?

• A. 4 × T✓
• B. 2 × T
• C. 3 × T
• D. 1 × T

Explanation: The fundamental mode of a closed-open organ pipe produces a wavelength that is four times the length of the pipe. This is because the closed end is a displacement node and the open end is a displacement antinode, leading to a quarter wavelength fitting into the pipe length. Hence, the full wavelength is 4 times the pipe length, T. The other options do not account for the correct relationship between the pipe length and the wavelength in a closed-open pipe.

Q159. During adiabatic expansion internal energy decreases by 2J, then work done in this process is:

• A. 2J✓
• B. 1J
• C. -1J
• D. -2J

Explanation: The work done during adiabatic expansion can be calculated using the First Law of Thermodynamics, which states that the change in internal energy (ΔU) is equal to the heat added to the system (Q) minus the work done by the system (W). Since this is an adiabatic process, there is no heat added or removed from the system (Q=0). Therefore, ΔU = -2 J (as the internal energy decreases by 2J).Thus, W = -ΔU = -(-2 J) = 2 J. The rest options have incorrect values

Q160. Michelson interferometer can be used to measure:

• A. Speed of sound
• B. Wavelength of sound
• C. Speed of light
• D. Wavelength of light✓

Explanation: Michelson's Interferometer uses the phenomena of interference to measure the wavelength of light from a source.

Q161. You stand on a spring scale on the floor of an elevator. Of the following, the scale shows the highest reading when the elevator:

• A. Moves upward with increasing speed✓
• B. Moves upward with decreasing speed
• C. Remains stationary
• D. Moves downward with increasing speed

Explanation: The correct answer is that the scale shows the highest reading when the elevator moves upward with increasing speed. This is because the elevator's upward acceleration adds to the gravitational force, increasing the normal force exerted on the scale. In physics terms, the apparent weight is the sum of the gravitational force (mg) and the force due to acceleration (ma), resulting in a higher reading on the scale.In contrast, moving upward with decreasing speed indicates downward acceleration, reducing the normal force. Remaining stationary results in no additional forces beyond gravity, reflecting your true weight. Moving downward with increasing speed causes downward acceleration, further decreasing the normal force and the scale reading.

Q162. Which thermodynamic temperature is equivalent to 501.850C?

• A. 775.00 K✓
• B. 774.85 K
• C. 228.85 K
• D. 228.70 K

Explanation: To convert from Celsius (C) to thermodynamic temperature, also known as Kelvin (K), you can use the formula:Kelvin (K) = Celsius (C) + 273.15So, to find the thermodynamic temperature equivalent to 501.85°C, you can do the following calculation:Kelvin (K) = 501.85 + 273.15Kelvin (K) = 775.00 KTherefore, 501.85°C is equivalent to 775.00 K.

Q163. The rate of change of momentum of a body falling freely under gravity is equal to its:

• A. Impulse
• B. Kinetic energy
• C. Power
• D. Weight✓

Explanation: Option D is correct. The rate of change of momentum of a body falling freely under gravity is equal to its weight. When an object is in free fall, the force of gravity is the only force acting on it, which can be expressed as its weight (mass * gravity). Therefore, according to Newton's second law, the rate of change of momentum (dp/dt) is equal to the gravitational force, synonymous with weight in this context.Why the other options are incorrect:Impulse: Although impulse is related to the change in momentum, it is not the rate of change of momentum; it is the product of force and the time during which the force acts.Kinetic Energy: Kinetic energy quantifies an object's energy due to motion but is not directly linked to the momentum change rate.Power: Power measures the rate of doing work, not the rate of change of momentum.

Q164. Drops X and Y, of the same oil, remained stationary in air in the same electric field. After the field was switched off, X fell more quickly than Y. which deduction can be made?

• A. X had a greater charge than Y✓
• B. Y had a greater charge than X
• C. Parallel but opposite
• D. Parallel, opposite and folded spirally.

Explanation: The correct answer is that X had a greater charge than Y. This conclusion is drawn from the observation that after the electric field was switched off, drop X fell more quickly than drop Y. The behavior of the drops in the electric field indicates that while the field was active, the electrostatic forces acting on each drop were balanced by the drag forces. Since X fell faster once the field was removed, it suggests that X must have had a greater charge to maintain equilibrium under the influence of the electric field. This indicates that the weight of the drops, which is proportional to the cube of their radii, was not sufficient to counteract the charge-induced forces on drop Y. Thus, drop X's greater charge allowed it to fall more rapidly once the electric field was no longer present.Other options are incorrect because they either contradict the observed behavior of the drops or are irrelevant to the relationship between the charges and the motion of the drops in the electric field.

Q165. What are the units of the ratio: specific latent heat of vaporization of water/ specific heat capacity of water

• A. K✓
• B. 1/K
• C. K2
• D. No unit

Explanation: K is the units of the ratio: specific latent heat of vaporization of water/ specific heat capacity of water .

Q166. The deuterium atom has _ quarks

• A. 3
• B. 6✓
• C. 9
• D. 12

Explanation: Correct. A deuterium atom consists of one proton and one neutron, and each of these contains three quarks:A proton has two up quarks and one down quark (uud).A neutron has one up quark and two down quarks (udd).So, the total number of quarks in deuterium is 3 (proton) + 3 (neutron) = 6 quarks.

Q167. The phase angle between two points in a medium is 4pi/5. What is the separation between these two points if the wavelength of the wave is 5m.

• A. 5/4 m
• B. 4pi m
• C. 2 m✓
• D. 10 m

Explanation: ΔФ = 2π/λ Δx 4π/5=2π/5 Δx ; Δx= 2m

Q168. A particle, held by a string whose other end is attached to a fixed point C, moves in a circle on a horizontal frictionless surface. If the string is cut, the angular momentum of the particle about the point: C.

• A. Increases
• B. Decreases
• C. Remains constant✓
• D. Changes direction but not magnitude

Explanation: Angular momentum is a conserved quantity in the absence of external torques. When the string is cut, the particle continues to move tangentially to its circular path. Since there is no external force or torque acting on the particle with respect to the fixed point C, the angular momentum remains constant.Option A is incorrect because without external torque, angular momentum cannot increase. Option B is incorrect for the same reason—it cannot decrease. Option C is correct because it reflects the principle of conservation of angular momentum. Option D is incorrect because while the particle's trajectory changes, the concept of angular momentum about a point doesn't involve changes in direction without external torque.

Q169. Which of the following furnaces is used for the production of wrought iron?

• A. Open hearth furnace✓
• B. Reverberatory furnace
• C. Bessemer converter
• D. Blast furnace

Explanation: A puddling furnace is used which is a type of an open hearth furnace, it is constructed to pull hot air over the iron without the fuel coming in direct contact with the iron. Therefore the correct answer will be A.

Q170. A mass accelerates uniformily when the resultant force acting on it:

• A. Is zero
• B. Is constant but not zero✓
• C. Increases uniformly with respect to time
• D. Is proportional to the displacement of the mass from a fixed point

Explanation: A mass accelerates uniformly when the resultant force acting on it is constant but not zero.

Q171. Moon is revolving around the earth, work done by the earth on the moon is

• A. Positive
• B. Zero✓
• C. Negative
• D. None of these

Explanation: B. The formula for work done on a body is; W = F × d cos θWhere,F = the force of gravitation applied by the earth.d = displacement between the two bodiesθ = the angle between F and dWhen the moon revolves around the earth, there is a 90° angle between the displacement of the moon and the gravitational force exerted by the earth.Putting θ = 90° in the equation,W = F × d cosBut, Cos 90° = 0So, W = 0

Q172. 12,32,72,152 _

• A. 312✓
• B. 325
• C. 515
• D. 613

Explanation: 12+20=3232+40=7272+80=152so 160 should be added in 152152+160=312

Q173. Complete the sequence:2, 15, 41, 80, _

• A. 111
• B. 120
• C. 121
• D. 132✓

Explanation: Find the differences between consecutive terms:15 - 2 = 1341 - 15 = 2680 - 41 = 39Notice the pattern in the differences: The differences are increasing by 13 each time (13, 26, 39).Find the next difference: The next difference would be 39 + 13 = 52.Find the next term in the sequence: Add the next difference to the last term: 80 + 52 = 132.Therefore, the next number in the sequence is 132.

Q174. 8, 10, 14, 18, _ , 34, 50 , 66:

• A. 24
• B. 25
• C. 26✓
• D. 27

Explanation: The series progresses as follows: starting from 8, we add 2 to get 10, then add 4 to get 14, again add 4 to get 18. The next step requires adding 8 to 18, resulting in 26. This fits the established pattern of increasing increments: +2, +4, +4, +8. The subsequent number in the series is then 34, followed by 50, and 66, which confirm the sequence's consistency. Options A, B, and D are incorrect as they do not adhere to this increment pattern.

Q175. What letter comes next in the following series? B D G K P

• A. C
• B. E
• C. B
• D. V✓
• E. Q

Explanation: B c DD e f GG h i j KK l m n o PP q r s t u V

Q176. Statements: 1. Blueberries cost more than strawberries. 2. Blueberries cost less than raspberries. 3. Raspberries cost more than strawberries and blueberries. If the first two statements are true, the third statement is:

• A. True✓
• B. False
• C. Uncertain
• D. None of these

Explanation: From the first two statements, we can establish the cost order: Raspberries > Blueberries > Strawberries. This directly confirms that raspberries cost more than both of the other fruits, making the third statement true.

Q177. The Emporium Mall has more stores than the Pakages Mall.The Amanah Mall has fewer stores than the Pakages Mall.The Emporium Mall has more stores than the Amanah Mall.If the first two statements are true, the third statement is

• A. True✓
• B. FALSE
• C. Uncertain
• D. None of these

Explanation: ExplanationFrom the first two statements, you know that the Emporium mall has the most stores, so the Emporium Mall would have more stores than the packages Mall.

Q178. Statement:The Management of School M has decided to give free breakfast from next academic year to all the students in its primary section through its canteen even though they will not get any government grant.Courses of Action:I. The school will have to admit many poor students who will seek admission for the next academic year.II. The canteen facilities and utensils have to be checked and new purchases to be made to equip it properly.III. Funds will have to be raised to support the scheme for years to come.

• A. Only II and III follows✓
• B. Only III and I follow
• C. Only I and II follow
• D. Only I follows

Explanation: Since the school has introduced the scheme without receiving any grant, it needs to pool up the funds and make adequate arrangements to keep the scheme going. So, only II and III follow.

Q179. Statement:The availability of imported fruits has increased in the indigenous market and so the demand for indigenous fruits has been decreased. Courses of Action:I. To help the indigenous producers of fruits, the Government should impose a high import duty on these fruits, even if they are not of good quality.II. The fruit vendors should stop selling imported fruits. So that the demand for indigenous fruits would increase.

• A. Only I follows
• B. Only II follows
• C. Neither I nor II follows✓
• D. Both I and II follow

Explanation: The ideas suggested in both I and II represent unfair means to cut competition. The correct way would be to devise methods and techniques such that the indigenous producers could produce better-quality fruits and make them available in the market at prices comparable with those of the imported ones. Hence, neither I nor II follow.

Q180. Verbal ReasoningStatements:(I) He has got cavities in his tooth (II) He eats too many chocolates

• A. Statement 1 is the cause and statement 2 is its effect.
• B. Statement 2 is the cause and statement 1 is its effect.✓
• C. Both statements are independent causes.
• D. Both statements are of a common cause.

Explanation: Statement 2 is the cause and statement 1 is its effect. Eating too many chocolates is a known cause of cavities due to the sugar content, which promotes bacterial growth and acid production. As a result, this leads to tooth decay and cavities. Statement 1 being the cause would not logically lead to statement 2. Additionally, the statements are not independent as they are directly related, nor do they share a common cause.