Federal Mdcat Mock Paper 3 — Solved Past Paper with Answers

Q1. Select the word with the closest meaning to the given word:Wrecked

• A. Defined
• B. Developed
• C. Ruined✓
• D. Registered

Explanation: To say something is wrecked means that it is destroyed or severely damaged. Therefore, C is the correct option.

Q2. You should stick _ your promise.Choose the best option to fill in the blank.

• A. By
• B. To✓
• C. With
• D. In

Explanation: The preposition “To” is the correct answer here as it is used as an infinitive of purpose.

Q3. Choose the correct option. The injured player was taken _ the field.

• A. Off✓
• B. Of
• C. Out
• D. In

Explanation: “Off” is used here as it shows disconnection from a person, place or object, i.e away from someone or something, in this case the field.

Q4. Neither they nor their friend _ solved the question.

• A. Has✓
• B. Have
• C. Was
• D. Were

Explanation: In 'neither-nor' constructions, the verb agrees with the subject closest to it. In this sentence, the subjects are 'they' and 'their friend.' Since 'friend' is closest to the verb and is singular, the verb 'has' is the correct choice, as it aligns with the singular subject. The option 'have' is incorrect as it would require a plural subject. 'Was' and 'were' are incorrect as they do not fit the present tense context.

Q5. He asked me _.

• A. How are you
• B. How was I
• C. How you are
• D. How I was✓

Explanation: The key to solving these questions is to read this sentence in your head while filling each option in the blank. The confusion here is between Options A and D. ‘how I was’ fits here well and how are you would have been used if this was being written as direct speech in quotation marks.

Q6. When your friend _, he'll be very tired.

• A. Arrived
• B. Arrives✓
• C. Will arrive
• D. Is arriving

Explanation: The correct answer is Option B: 'Arrives'. In this sentence, 'arrives' is used to describe an action that will happen in the future, following the structure of a conditional sentence. The future aspect is conveyed by 'he'll be very tired' (he will be very tired). Option A 'arrived' is incorrect because it is in the past tense, not fitting the future context. Option C 'will arrive' is unnecessary as the sentence already implies a future event. Option D 'is arriving' suggests a current ongoing action, which is not suitable here.

Q7. Pick up the wrong one:The beautiful and the most attractive picture was hanged on the wall.

• A. Beautiful
• B. The most
• C. Was
• D. Hanged✓

Explanation: Option D is the correct choice because 'hanged' is used incorrectly in the context of hanging an object. The correct form should be 'hung', which is the past tense of 'hang' typically used for inanimate objects like pictures. 'Hanged' is reserved for referring to execution by hanging. The other options, 'beautiful', 'the most', and 'was', are all used correctly in the sentence.

Q8. The sentence which has one dependent and one independent clause is called a:

• A. Compound sentence
• B. Complex sentence✓
• C. Compound complex sentence
• D. Exclamatory sentence

Explanation: The correct answer is: complex sentence.A complex sentence is a sentence that contains one independent clause (main clause) and one or more dependent clauses (subordinate clauses). The independent clause can stand alone as a complete sentence, while the dependent clause cannot.Example: "I went to the store because I needed milk." (Independent clause: "I went to the store"; Dependent clause: "because I needed milk")

Q9. Fill in the blanks with the most appropriate option. When we went to cinema, the film _.

• A. Already started
• B. Had already started✓
• C. Would already start
• D. Started already

Explanation: The other options are wrong as 'when we went' indicates the use of the past tense. The correct answer is B) had already started.

Q10. The oxygen-binding protein present in skeletal muscles is:

• A. Globin
• B. Glycogen
• C. Myoglycogen
• D. Myoglobin✓

Explanation: Myoglobin is a low molecular weight oxygen-binding heme protein that is found exclusively in the heart and skeletal muscle cells.

Q11. Which of the following helps in maintaining balance?

• A. Hypothalamus
• B. Medulla Oblongata
• C. Cerebellum✓
• D. Pons

Explanation: The cerebellum is a part of the hindbrain that helps in maintaining the posture and balance of the body. The hypothalamus has several endocrine functions involving thermoregulation. Pons regulate the sleep-wake cycle. Medulla Oblongata controls involuntary movements such as breathing, heart rate, etc.

Q12. Pulmonary veins supply blood to the heart chamber:

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

Explanation: The oxygenated blood is brought back to the heart by the pulmonary veins which enter the left atrium. From the left atrium, blood flows into the left ventricle. The left ventricle pumps the blood to the aorta which will distribute the oxygenated blood to all parts of the body.

Q13. Sensation of pleasure, punishment, or sexual arousal are stimulated by the parts of the brain:

• A. Hippocampus
• B. Hypothalamus
• C. Amygdala✓
• D. Thalamus

Explanation: The amygdala controls the sensation of pleasure, punishment, or sexual arousal. The hippocampus has a major role in learning and memory. The hypothalamus is considered to be a link structure between the nervous and the endocrine system; its main function is to maintain the homeostasis of the body. The thalamus has several functions, such as relaying of sensory signals, including motor signals, to the cerebral cortex and the regulation of consciousness, sleep, and alertness.

Q14. The word glycogenesis means, the conversion of:

• A. Glucose to glycogen✓
• B. Lactic acid to glycogen
• C. Glycogen to glucose
• D. Amino acid to glycogen

Explanation: Glycogenesis refers to the conversion of glucose to glycogen, which is a way of storing glucose for future energy needs. This process occurs when there is an excess of glucose in the blood, allowing it to be stored in the liver and muscle cells. Option A is correct as it directly describes this process. Option B describes the Cori cycle, where lactic acid is eventually converted back to glucose, not directly to glycogen. Option C describes glycogenolysis, the opposite of glycogenesis, where glycogen is broken down into glucose. Option D describes a multi-step process starting with amino acids being converted to glucose, which can then be stored as glycogen, but this is not direct glycogenesis.

Q15. Germ Theory of disease was proposed by:

• A. Leeuwenhoek
• B. Louis Pasteur
• C. Walther Flemming
• D. Robert Koch✓
• E. Edward Jenner

Explanation: Option A: Antonie van Leeuwenhoek, a Dutch microscopist, was the first person to observe microorganisms in the 17th century. Option B: Louis Pasteur, a French chemist and microbiologist, conducted experiments that showed that microorganisms can cause fermentation and spoilage. He also developed vaccines for rabies and anthrax. Option C: Walther Flemming, a Danish biologist, discovered chromosomes and showed that they are made up of DNA. Option D: The germ theory of disease was proposed by Robert Koch. He is a German physician and microbiologist who is considered the "father of bacteriology". In the late 19th century, Koch developed four criteria, now known as Koch's postulates, to establish that a specific microorganism causes a specific disease. These criteria are still used today to confirm the cause of a disease. The germ theory of disease has revolutionized the way we understand and treat disease. It has led to the development of vaccines, antibiotics, and other treatments that have saved millions of live Option E: Edward Jenner, an English physician, developed the first vaccine against smallpox.

Q16. A woman with normal colour vision, whose father was red green colour blind, married a red green colour blind man. What is the probability of her born child being red green colour blind?

• A. 1.0
• B. 0.75
• C. 0.50✓
• D. 0.25

Explanation: Males have 1 X chromosome and 1 Y chromosome, and females have 2 X chromosomes. The genes that can give you red-green colour blindness are passed down on the X chromosome.The woman’s father is red-green colour blind. Since the woman got one of her X chromosomes from her father this means that she is a carrier. As it can be seen from the table the probability of having a colourblind child is 0.5%

Q17. In aerobic respiration most of the ATP is synthesized during:

• A. Oxidation of pyruvic acid
• B. Electron transport chain✓
• C. Krebs cycle
• D. Glycolysis

Explanation: The maximum ATP yield for a molecule of glucose is around 30-32 ATP. During glycolysis, from one glucose molecule, net 2 ATP molecules are produced. During oxidation of Pyruvic acid, no ATPs are produced. During Krebs cycle, for one glucose molecule, 2 ATPs are produced. Beyond those four, the remaining ATP all come from ETC during oxidative phosphorylation. The correct answer is, therefore, B.

Q18. Number of bones in skull is:

• A. 8
• B. 14
• C. 22✓
• D. 33

Explanation: The cranium has 8 bones. 14 bones are found in the fingers of each hand and also in the toes of each foot. The spine is made up of 33 vertebrae. Vertebrae are the 33 individual bones that interlock with each other to form the spinal column. The human skull contains 22 bones. The correct answer is, therefore, C.

Q19. Gigantism in human beings is caused due to over secretion of:

• A. Thyrotropin
• B. Corticotropin
• C. Somatotropin✓
• D. Prolactin

Explanation: Gigantism occurs when a child’s pituitary gland makes too much growth hormone, which is also known as somatotropin. Corticotropin-releasing hormone (CRH), also called corticotropin-releasing factor (CRF), is a peptide hormone that activates the synthesis and release of adrenocorticotropic hormone (ACTH) from the pituitary gland. In this way, CRH affects our response to stress, addiction and depression, amongst others. Prolactin is a hormone made by the pituitary gland, a small gland at the base of the brain. Prolactin causes the breasts to grow and make milk during pregnancy and after birth. Thyroid-stimulating hormone/Thyrotropin is a hormone produced by anterior pituitary gland that stimulates the thyroid gland to produce thyroxine, and then triiodothyronine which stimulates the metabolism of almost every tissue in the body. Therefore, the correct answer is C.

Q20. The condition in which one of more genes that have no allelic counterpart is known as:

• A. Homozygous
• B. Hemizygous✓
• C. Heterozygous
• D. Incomplete dominance

Explanation: Hemizygous means having only a single copy of a gene instead of the customary two copies. All the genes on the single X chromosome in the male are hemizygous. Homozygous means having 2 identical alleles of a particular gene. Heterozygous means having 2 different alleles of a particular gene. Incomplete dominance is a form of Gene interaction in which both alleles of a gene at a locus are partially expressed, often resulting in an intermediate or different phenotype. The correct answer is, therefore, B.

Q21. A woman can be bald only when she is

• A. Homozygous dominant
• B. Heterozygous
• C. Homozygous recessive✓
• D. None of these

Explanation: Pattern baldness is a sex-influenced trait, meaning its expression differs between males and females. In men, it is an autosomal dominant trait, allowing baldness to occur with just one dominant allele. However, in women, it is an autosomal recessive trait, which means baldness occurs only if the woman has two recessive alleles (homozygous recessive). This is why a woman can only be bald if she is homozygous recessive. The other genotypes, homozygous dominant and heterozygous, result in the dominant allele masking the recessive allele, preventing baldness in females.

Q22. Nictitating membrane is found in the _ and performs _function.

• A. Eyes … cleaning and protection✓
• B. Brain … processing
• C. Feet … balance
• D. Bones … structure

Explanation: The nictitating membrane is a semi-transparent third eyelid found in some animals, such as birds, reptiles, and some mammals. It serves to protect the eye from debris and helps keep it moist while allowing for vision. The other options are incorrect because the nictitating membrane is not involved in brain processing, balance, or structural support, which are functions of other body parts.

Q23. Eukaryotic, multicellular, and consumers belong to _ kingdom.

• A. Monera
• B. Protista
• C. Fungi
• D. Animalia✓

Explanation: Kingdom Monera: It comprises unicellular, prokaryotic organisms, which can be heterotrophic or autotrophic, having no well-defined nucleus and no organelles.Kingdom Protista: Protists are eukaryotic, unicellular organisms They can be autotrophs or heterotrophs.Kingdom Fungi: Fungi can be single-celled or very complex multicellular organisms. All fungi are heterotrophic, which means that they get the energy they need to live from other organisms.They are eukaryotes.Kingdom Animalia: They are eukaryotic, multicellular, and heterotrophic.

Q24. Which substance might include this molecule?

• A. Cellulose
• B. Cholesterol
• C. Glycerol✓
• D. Insulin

Explanation: Glycerol has three OH groups as it forms bonds with three fatty acid molecules.

Q25. How many fatty acid molecules are normally present in a fat or oil molecule?

• A. 1
• B. 2
• C. 3✓
• D. 4

Explanation: If we talk about a fat molecule, we are essentially discussing a lipid molecule that comprises glycerol and fatty acids linked via esterification. Since glycerol has three hydroxyl groups and a fatty acid molecule has only one carboxylic group, we need three fatty acid molecules to bind to the three hydroxyls, OH groups on the glycerol molecule.

Q26. Retrovirus cause diseases in:

• A. Rodents
• B. Fowls
• C. Cats
• D. All of these✓

Explanation: The correct answer is d) All of these. Retroviruses have been identified to cause diseases in rodents, fowls, and cats. These viruses can have varying effects on different species, but they are known to be pathogenic and can lead to various health issues.

Q27. Sperms are produced in:

• A. Urethra
• B. Sperm dust
• C. Pancreas
• D. Testes✓

Explanation: The testes are the male reproductive organs responsible for producing sperm through a process called spermatogenesis.

Q28. Right ventricle connects with lungs by:

• A. Aorta
• B. Pulmonary veins
• C. Pulmonary artery✓
• D. Dorsal aorta

Explanation: The pulmonary artery leaves the right ventricle and takes blood to the lungs. Pulmonary vein brings blood back from the lungs to the left atrium of the heart. Aorta connects the right ventricle to pump blood to the body. The correct answer is, therefore, C.

Q29. A muscle with characters like a spontaneous contraction, one nucleus per cell, and no control over contraction is most likely:

• A. None of these
• B. Cardiac muscle✓
• C. Skeletal muscle
• D. Smooth muscle

Explanation: The correct answer is Cardiac muscle. Cardiac muscle has spontaneous contractions, typically contains one nucleus per cell, and operates under involuntary control, which fits the criteria given in the question. It is specifically found in the heart and is equipped with intercalated discs that enable synchronized contractions, making it distinct from other muscle types.Skeletal muscle is incorrect because it is under voluntary control and has multiple nuclei per cell. Smooth muscle (sometimes called visceral muscle) is involuntary and single nucleated but doesn't exhibit spontaneous contractions in the same context as cardiac muscle. The option None of these is incorrect because cardiac muscle fits the description.

Q30. Gray matter of spinal cord does not contain:

• A. Cell bodies of sensory neurons✓
• B. Cell bodies of interneurons
• C. Axons of interneurons
• D. Cell bodies of motor neurons

Explanation: Gray matter, the inner matter of the spinal cord does not contain cell bodies of sensory neurons.

Q31. Porins are present in:

• A. Mitochondria and golgi apparatus
• B. Mitochondria and chloroplast✓
• C. Mitochondria and ribosomes
• D. Golgi apparatus and chloroplast

Explanation: Mitochondria: The outer mitochondrial membrane contains porins called Voltage-Dependent Anion Channels (VDACs), which allow the passage of ions and small molecules into the intermembrane space.* Chloroplasts: Porins are also present in the outer membrane of chloroplasts, facilitating the transport of metabolites and ions across the membrane.

Q32. As the pH of blood decreases, H+ ions increase, which combine with the protein part of hemoglobin to reduce its ability to bind with:

• A. O2✓
• B. CO2
• C. CO
• D. H2

Explanation: If the pH of blood is lower than normal (normal physiological pH is 7.4), then the haemoglobin does not bind oxygen as well. In other words, the lower the pH, the more Hydrogen ions, the higher the carbon dioxide level and the LESS affinity Hemoglobin has for oxygen. The opposite is also true: the higher the pH lower the H+ ion concentration, the lower the carbon dioxide level, and the greater the affinity of haemoglobin for oxygen.

Q33. On receiving the news of the sudden demise of a close friend; which is the most probable hormone that is secreted at that time?

• A. Prostaglandin
• B. Growth inhibitors
• C. Estrogen
• D. Adrenaline✓
• E. Thyroxin

Explanation: When a close person dies, this can cause the adrenal glands to pour adrenaline hormones into the bloodstream due to anxiety that subsides the emotional stress.

Q34. Which combination describes a triglyceride?

• A. Option A✓
• B. Option B
• C. Option C
• D. Option D

Explanation: Triglyceride being nonpolar do not dissolve in water hence are insoluble in water; they do store a lot of energy in them; they do hydrolyze to release water, and being non-polar they can dissolve in organic solvents.Restriction enzyme, also called restriction endonuclease, a protein produced by bacteria that cleaves DNA at specific sites along the molecule. In the bacterial cell, restriction enzymes cleave foreign DNA, thus eliminating infecting organisms.

Q35. First step of viral replication is:

• A. Entry
• B. Assembly
• C. Uncoating
• D. Adsorption or Attachment✓

Explanation: Viral infections follow similar steps in the virus replication cycle: attachment or adsorption, penetration, uncoating, replication, assembly, and release.

Q36. The axial skeleton of an adult human includes:

• A. The skull, pectoral girdle, and ribs
• B. The skull, ribs, and bones of arms and legs
• C. The pectoral and pelvic girdles
• D. The ribs, the skull, the sternum, and the vertebrae✓

Explanation: The axial skeleton involves the ribs, skull, sternum, and vertebrae.

Q37. Which of the following produce response?

• A. Effectors✓
• B. Nerve
• C. Stimulators
• D. Brain

Explanation: Effectors are organs like muscles or glands that produce a response to a stimulus by contracting or secreting substances when signaled by the nervous or endocrine system.

Q38. What explains the effect on a red blood cell of being placed into pure water?

• A. Less water leaves the cell than enters it, so the cell shrinks.
• B. More water enters the cell than leaves it, so the cell swells and bursts.✓
• C. Water enters the cells and none leaves it, so the cell swells and bursts.
• D. Water enters the cell and more leaves it, so the cell shrinks.

Explanation: b) More water enters the cell than leaves it, so the cell swells and bursts:This option is partially correct. When a red blood cell is placed into pure water, water molecules will move into the cell by osmosis. The influx of water will cause the cell to swell. However, under normal conditions, a red blood cell has a flexible membrane that can stretch to accommodate the influx of water, preventing the cell from bursting.

Q39. Which statement about a triglyceride molecule are correct?1. It always contains unsaturated hydrocarbon tails2. It is formed using ester bonds3. It does not form hydrogen bonds4. It contains a hydrophilic glycerol head

• A. 1, 2 and 3
• B. 2, 1 and 4
• C. 1 and 4 only
• D. 2 and 3 only✓

Explanation: Triglycerides are formed by linking fatty acids with an ester linkage to three alcohol groups in glycerol. Triglycerides are hydrophobic and so insoluble in water. The charges are evenly distributed around the molecule so hydrogen bonds to not form with water molecules. The correct answer is, therefore, D.

Q40. In term of enzyme actions, 'maximum temperature' refers to a temperature at which:

• A. A. Enzymes start to denature✓
• B. B. Enzymes start to re-nature
• C. C. Enzymes work best
• D. D. Enzymes are reactivated

Explanation: The term 'maximum temperature' indicates the point at which enzymes begin to denature, meaning they lose their functional shape due to heat (Option A). When enzymes denature, they can no longer catalyze reactions effectively. Option B is incorrect because enzymes do not start to re-nature at maximum temperatures; they are still denaturing. Option C is misleading, as enzymes do not work optimally at maximum temperature but rather at their specific optimal temperature. Option D is also incorrect since reactivation occurs after denaturation under favorable conditions, not at the point of maximum temperature.

Q41. The chemical which regulates the enzymatic activity is:

• A. Activator
• B. Inhibitor
• C. Substrate
• D. Both A and B✓

Explanation: Enzymes can be regulated by other molecules that either increase or reduce their activity. Molecules that increase the activity of an enzyme are called activators, while molecules that decrease the activity of an enzyme are called inhibitors.

Q42. Virus recognize host through:

• A. Envelope
• B. DNA
• C. Capsid
• D. Protein Coat✓

Explanation: A virus’ protein coat contains receptors. The virus recognizes and binds to a host cell via a receptor. The virus or its genetic material then enters the host cell. The envelope itself is derived from the host.

Q43. Cell surface markers are

• A. Lipoproteins
• B. Glycolipids
• C. Sphingolipids
• D. Glycoproteins
• E. both b and d✓

Explanation: The correct answer is both b and d because both glycolipids and glycoproteins are classified as cell surface markers. Glycolipids are lipids with carbohydrate groups attached, found on the outer surface of cell membranes, playing critical roles in cell recognition and signaling. Glycoproteins, on the other hand, are proteins that have carbohydrates covalently bonded to them, and they also function in recognition and signaling processes at the cell surface. In contrast, lipoproteins primarily function in lipid transport in the bloodstream and are not cell surface markers. Sphingolipids, while important for membrane structure and signaling, are not specifically known as markers for cell recognition.

Q44. Trypsinogen is activated by:

• A. Chymotrypsin
• B. Enteropeptidase✓
• C. Trypsin
• D. HCl

Explanation: Trypsinogen is activated by enteropeptidase, which converts it into trypsin, a crucial step in protein digestion within the small intestine. Chymotrypsin is an enzyme activated by trypsin, but it does not participate in activating trypsinogen. Trypsin, once formed, can further activate additional trypsinogen molecules, but it is not the initial activator. HCl is involved in a separate digestive process in the stomach, converting pepsinogen to pepsin, and does not play a role in the activation of trypsinogen.

Q45. Role of lysosomes include:

• A. Store hydrolytic enzymes
• B. Perform autophagy
• C. Destruction of cell
• D. All of above✓

Explanation: Lysosomes store hydrolytic enzymes, which play their role in autophagy and destruction of old cells. Hence, the correct option is D.

Q46. The haploid number of chromosomes in human beings:

• A. 4
• B. 10
• C. 24
• D. 23✓

Explanation: The correct answer is 23. In humans, somatic cells contain 46 chromosomes, which is the diploid number. Gametes, such as sperm and eggs, contain the haploid number of chromosomes, which is half of the diploid number, resulting in 23 chromosomes. This ensures that when fertilization occurs, the resultant zygote will have 46 chromosomes. The other options are incorrect because they do not reflect the accurate division of the diploid number in humans.

Q47. Which of the following correctly shows structures which are found in a eukaryotic cell? (Yes = present ; No = absent)

• A. Option A
• B. Option B
• C. Option C
• D. Option D
• E. Option E✓

Explanation: The question asks for eukaryotic cells, which possess a nucleus as well as other membrane bound organelles such as mitochondria, lysosomes, golgi apparatus, endoplasmic reticulum in addition to (80S) ribosomes. Only option E fulfills this criteria, as all other options have one or more of the components missing.

Q48. The RNA found in Ribosomes is:

• A. mRNA
• B. rRNA✓
• C. tRNA
• D. Polysome
• E. Genes

Explanation: Ribosomal RNA (rRNA) is the most abundant type of RNA in cells. It is found in ribosomes, which are the cellular structures that are responsible for protein synthesis. rRNA makes up about 80% of the mass of ribosomes. They are made up of two subunits, a large subunit and a small subunit. Both subunits contain rRNA, as well as a number of proteins. It is involved in the assembly of ribosomes and in the translation of mRNA into proteins.

Q49. In humans,_ is responsible for producing cell's hydrogen peroxide.

• A. Lysosomes
• B. Mitochondria
• C. Peroxisomes✓
• D. glyoxysome

Explanation: The main chemical produced by oxidation in peroxisomes is the very cytotoxic (cell toxic) hydrogen peroxide. Fortunately peroxisomes produce copious amounts of the enzyme catalase and this helps break down hydrogen peroxide to water and oxygen.

Q50. HIV-I protease is an enzyme produced by the HIV virus. Two identical chains of 99 amino acids form the enzyme. In each chain, amino acids 25, 25 and 27 in the sequence form part of the active site. Which orders of protein structure control the shape of the active site?

• A. Primary, secondary, tertiary and quaternary✓
• B. Primary, secondary and tertiary only
• C. Primary and quaternary only
• D. Quaternary only

Explanation: The correct answer is that primary, secondary, tertiary, and quaternary structures all control the shape of the active site. The primary structure refers to the sequence of amino acids, which is critical for the positioning of the active site residues. The secondary structure involves local folding patterns like alpha-helices and beta-sheets that contribute to the protein's overall shape. The tertiary structure is the overall 3D shape of the single polypeptide chain, which affects the position and orientation of the active site. Finally, the quaternary structure is essential because the enzyme consists of two identical chains, and their interaction helps form the functional enzyme with a properly oriented active site. Other options fail to incorporate all these necessary levels of structure.

Q51. The reflex arc, which is made of two neurons is known as:

• A. Monosynaptic reflex arc✓
• B. Disynaptic reflex arc
• C. Polysynaptic reflex arc
• D. Asynaptic reflex arc

Explanation: The correct answer is the Monosynaptic reflex arc. It consists of only two neurons: a sensory neuron and a motor neuron, with a single synapse between them. This allows for a quick reflex action, such as the knee-jerk reflex. In contrast, the Disynaptic reflex arc involves an additional interneuron, leading to two synapses, and the Polysynaptic reflex arc involves multiple interneurons and synapses, allowing for more complex reflex actions. The Asynaptic reflex arc is not a valid term, as all reflex arcs require at least one synapse to function.

Q52. The life span of RBC is:

• A. 100 days
• B. 110 days
• C. 120 days✓
• D. 130 days

Explanation: This is a standard answer. Lifespan of RBCs is approximately 120 days.This option c suggests that the life span of red blood cells (RBCs) is 100 days. In humans, the average life span of RBCs is indeed around 100-120 days. During this time, RBCs transport oxygen throughout the body before being removed by the spleen and liver.

Q53. What describes a non-specific immune response?

• A. Activation of killer T lymphocytes by infected cells
• B. Cloning of B lymphocytes to form plasma cells
• C. Ingestion of a bacterial cell by a neutrophil✓
• D. Presentation of antigen on the cell surface of macrophages

Explanation: c) Ingestion of a bacterial cell by a neutrophil:This option describes a non-specific immune response. Neutrophils are a type of white blood cell and part of the innate immune system. They are capable of engulfing and destroying pathogens, such as bacteria, through a process called phagocytosis. This is a non-specific response as neutrophils can target a wide range of pathogens without requiring prior exposure.

Q54. Which of the following is found at the end of long bones, in the nose, larynx, and trachea?

• A. Elastic cartilage
• B. Fibrous cartilage
• C. Perichondrium
• D. Hyaline cartilage✓

Explanation: Hyaline cartilage is the most abundant type of cartilage and is found in the nose, ears, trachea, larynx, and smaller respiratory tubes.Fibrocartilage is found in vertebral discs and ligaments.Elastic cartilage is found in the external ear and epiglottis.

Q55. High temperature stops enzyme activity because enzymes:

• A. Dissolve
• B. Ionize
• C. Denature✓
• D. React with substrate

Explanation: Excess heat breaks hydrogen and ionic bonds ---> enzyme loses shape ---> inactive.

Q56. Identify the tricuspid valve:

• A. A✓
• B. B
• C. C
• D. D

Explanation: Tricuspid has 3 valves which are only present in A.

Q57. Identify the bicuspid valve:

• A. A
• B. B✓
• C. C
• D. D

Explanation: Bicuspid valve has 2 flaps which is present in B.

Q58. The walls of atria and the walls of ventricles are relaxed during:

• A. Systole
• B. Diastole✓
• C. Atrial systole
• D. Ventricular systole

Explanation: Diastole is the phase of relaxation in the cardiac cycle. During diastole, the heart chambers relax and fill with blood.

Q59. As the atria are filled with blood, they become distended and have:

• A. More pressure than ventricles✓
• B. Same pressure as ventricles
• C. Less pressure than ventricles
• D. Less volume than ventricles

Explanation: When atria are filled with blood and ventricles are empty, atria have more pressure than ventricles.

Q60. 'Lubb' sound is produced by closure of:

• A. Outlet valves
• B. Atrioventricular valves✓
• C. Semilunar valves
• D. Inter ventricular valves

Explanation: "Lubb" sound is produced when inlet valves or atrioventricular valves close and their flaps strike with each other.

Q61. 'Dubb' sound is produced by the closure of:

• A. Bicuspid valves
• B. Tricuspid valves
• C. Bicuspid and tricuspid valves
• D. Semilunar valves✓

Explanation: The "dubb" sound is produced by the closure of the aortic and pulmonary valves, which are the semilunar valves. The bicuspid and tricuspid valves are atrioventricular valves, and they produce the "lub" sound.

Q62. In one's life, heart contracts_without stopping.

• A. 2-5 billion times✓
• B. 1-5 billion times
• C. 2-5 million times
• D. 1.5 million times

Explanation: The human heart contracts continuously, averaging 2–5 billion beats across a normal lifespan.

Q63. These hormones perform antagonistic function EXCEPT:

• A. Growth Hormone – Somatostatin
• B. Calcitonin – Parathyroid
• C. Adrenaline – Noradrenaline✓
• D. Insulin – Glucagon

Explanation: A is incorrect because somatostatin inhibits the release of growth hormone from the pituitary gland. B is incorrect because calcitonin decreases blood Ca2+ levels while parathormone increases blood calcium levels. D is incorrect because insulin decreased blood glucose concentration and glucagon raises blood glucose concentration. Adrenaline and noradrenaline are both involved in the fight or flight response during times of emergency. Hence, they are not antagonistic.

Q64. It is the smallest eukaryote:

• A. Virus
• B. Bacteria
• C. Plasmodium✓
• D. Sponge

Explanation: Plasmodium belongs to the kingdom Protozoa which are Eukaryotes and are microscopic.Viruses' classification to even living things is in debate. Bacteria are prokaryotes. Sponges are found underwater and are visible by the naked eye.

Q65. Hormones called gonadotropins are released by which gland?

• A. Ovaries
• B. Hypothalamus
• C. Pituitary✓
• D. Testes

Explanation: Gonadotropins are released by the pituitary gland. Examples include LH, FSH etc.

Q66. Which of the following ideas was not part of Charles Darwin’s theory of evolution by natural selection?

• A. Organisms produce more off springs than the environment can support
• B. Variation between individuals arises by gene mutation✓
• C. Only those individuals best adapted by environment survive and reproduce
• D. Individuals compete for scarce resources

Explanation: The idea that was not part of Charles Darwin's theory of evolution by natural selection is Option B: Variation between individuals arises by gene mutation. While Darwin acknowledged the existence of variation, he did not have a detailed understanding of the genetic mechanisms behind it, such as gene mutations.

Q67. Evolution of kiwi, hooves of modern horse, webbed feet of duck, and loss of teeth in whale were all explained in detail by:

• A. Lamarck✓
• B. Darwin
• C. Weismann
• D. De Vries

Explanation: Lamarckism is a theory of evolution based on the principle that physical changes in organisms during their lifetime. Examples include evolution of kiwi, foot of modern horse, webbed feet of duck, and loss of teeth in whale.

Q68. Which of the following is NOT TRUE about interferons?

• A. Belong to cytokines
• B. Activate natural killer cells
• C. Activate immune cells
• D. Secrete interleukin✓

Explanation: Interferons (IFNs) are a broad class of cytokines that are part of your natural defenses. They tell your immune system that germs or cancer cells are in your body. And they trigger killer immune cells to fight those invaders. Interferons got their name because they "interfere" with viruses and keep them from multiplying.

Q69. Intrinsic factor secreted by parietal cells of stomach mucosa helps in:

• A. Vitamin B12 absorption✓
• B. Protein digestion
• C. Carbohydrate breakdown
• D. Bowel movement

Explanation: Intrinsic factor plays a crucial role in the transportation and absorption of the vital micronutrient vitamin B12.

Q70. A mammalian cell contains 70% of:

• A. DNA
• B. Protein
• C. RNA
• D. Water✓

Explanation: (d) Water (Correct Answer) – Water is the most abundant component of a mammalian cell, making up around 70% of its mass

Q71. Removal of the proximal convoluted tubule from the nephron will result in:

• A. No change in the quality and quantity of urine
• B. No urine formation
• C. More diluted urine✓
• D. More concentrated urine

Explanation: The correct answer is that urine would be more diluted. The proximal convoluted tubule (PCT) is essential for reabsorbing a significant portion of water and solutes like glucose, amino acids, and sodium. Its removal would lead to decreased reabsorption, resulting in urine with higher water content. Option A is incorrect because the PCT's absence does affect urine composition and volume. Option B is incorrect as urine formation is a collective effort of the nephron's sections. Option D is incorrect because the removal of the PCT means less water reabsorption, leading to more diluted—not concentrated—urine.

Q72. Immunity is a capacity to do following things EXCEPT:

• A. Recognition of foreign pathogens
• B. Effective and timely elimination of invaders
• C. Mobilization of immune cells and their products
• D. Blockage of entry of pathogens✓

Explanation: Blockage is not responsibility of immune system rather it is carried out by physical barriers.

Q73. The introduction of t-­DNA into plants involves:

• A. Exposing the plants to cold for a brief period
• B. Allowing the plant roots to stand in water
• C. Infection of the plant by Agrobacterium tumefaciens✓
• D. Altering the pH of the soil and then heat­ shocking the plants.

Explanation: Ti plasmid (tumor inducing) from the soil bacterium Agrobacterium tumefaciens is effectively used as a vector for gene transfer to plant cells. The part of Ti plasmid transferred into plant cell DNA is called the T­-DNA. This T-­DNA, with desired DNA spliced into it, is inserted into the chromosomes of the host plant where it produces copies of itself, by migrating from one chromosomal position to another at random. Such plant cells are then cultured, induced to multiply, and then differentiate to form plantlets. Transferred into the soil, the plantlets grow into mature plants, carrying the foreign gene, expressing throughout the new plant.

Q74. Lungs are made up of air­filled sacs, the alveoli. They do not collapse even after forceful expiration because of

• A. Inspiratory reserve volume
• B. Tidal volume
• C. Expiratory reserve volume
• D. Residual volume✓

Explanation: Even after a forceful expiration, a certain amount of air always remains in the lungs. This is called residual volume. It prevents the alveoli from collapsing completely, ensuring continuous exchange of gases (O₂ and CO₂) between breaths.

Q75. The partial pressure of oxygen in the alveoli of the lungs is:

• A. Equal to that in the blood
• B. More than that in the blood✓
• C. Less than that in the blood
• D. Less than that of carbon dioxide.

Explanation: The partial pressure of oxygen in the alveoli is higher than in the blood, facilitating the diffusion of oxygen from the alveoli into the blood, where it can be transported by hemoglobin to tissues throughout the body.

Q76. Reduction in pH of blood will directly cause which of the following?

• A. Decrease the affinity of haemoglobin with oxygen✓
• B. Release bicarbonate ions by the liver
• C. Reduce the rate of heart beat
• D. Reduce the blood supply to the brain.

Explanation: A reduction in blood pH (an increase in acidity) is typically associated with a condition called acidosis. In acidosis, the affinity of hemoglobin for oxygen decreases. This means that hemoglobin is less effective at binding with oxygen, which can lead to impaired oxygen transport to tissues.

Q77. Lungs are enclosed in:

• A. Periosteum
• B. Perichondrium
• C. Pericardium
• D. Pleural membrane✓

Explanation: It consists of two layers: the visceral pleura, which covers the lungs, and the parietal pleura, which lines the chest cavity. These layers form the pleural cavity, a fluid-filled space that allows the lungs to move smoothly during respiration.

Q78. At high altitude, the RBCs in the human blood will :

• A. Increase in number✓
• B. Decrease in number
• C. Increase in size
• D. Decrease in size

Explanation: This statement is accurate. At high altitudes, where the oxygen concentration in the air is lower, the body's response includes an increase in the number of red blood cells (RBCs). This is known as polycythemia. It's an adaptive mechanism to improve oxygen-carrying capacity, helping to transport more oxygen to body tissues.

Q79. Although much CO2 is carried in blood, yet blood does not become acidic, because :

• A. CO2 is continuously diffused through the tissues and is not allowed to accumulate
• B. In CO2 transport, blood buffers play an important role✓
• C. CO2 is absorbed by the leucocytes
• D. CO2 combines with water to form H2CO3 which is neutralized by NaCO3 .

Explanation: Even though a large amount of carbon dioxide is carried in the blood, it does not make the blood acidic because blood contains buffer systems, mainly bicarbonate ions, that neutralize excess hydrogen ions formed during CO₂ transport.

Q80. A muscuarly controlled hinge, like action and serves as a lid which automatically covers the opening of the larynx is called:

• A. Epiglottis✓
• B. Esophegeal sphineter
• C. Uvula
• D. Respiratory valve

Explanation: The epiglottis is a flap of cartilage that acts like a lid over the opening of the larynx. Its hinge-like action, controlled by muscles, automatically closes during swallowing to prevent food and liquid from entering the respiratory tract.

Q81. A cavity bounded by the ribs and diaphragm is called:

• A. Abdominal cavity
• B. Thoracic cavity✓
• C. Pelvic cavity
• D. Pleural cavity

Explanation: The cavity bounded by the ribs and diaphragm is called the thoracic cavity, or chest cavity. It is a large, hollow space that contains the heart, lungs, major blood vessels, and other important structures of the respiratory and cardiovascular systems. The thoracic cavity is separated from the abdominal cavity by the diaphragm, which is a thin sheet of muscle that helps to control breathing by contracting and relaxing.

Q82. The main objective of the production/use of herbicide-resistant GM crops is to:

• A. Encourage eco­friendly herbicides
• B. Reduce herbicide accumulation in food articles for health safety✓
• C. Eliminate weeds from the field without the use of manual labour
• D. Eliminate weeds from the field without the use of herbicides.

Explanation: Genetic engineering has helped to develop such transgenic crop plants which are resistant to herbicides so that they are not damaged when farmers spray herbicides in the fields. Herbicide resistant plants have been developed in such a way that they continue to produce normal crop yield and at the same time remain unaffected by the activity of herbicides. These plants also reduces the use of weeding labour, farmer’s cost and increases yield.

Q83. The bacterium Bacillus thuringiensis is widely used in contemporary biology as:

• A. Insecticide✓
• B. Agent for production of dairy products
• C. Source of industrial enzyme
• D. Indicator of water pollution

Explanation: Soil bacterium Bacillus thuringiensis produces proteins that kill certain insects like lepidopterans (tobacco budworm, armyworm), coleopterans (beetles), and dipterans (flies, mosquitoes). B. thuringiensis forms some protein crystals which contain a toxic insecticidal protein. This toxin does not kill the Bacillus (bacterium) because it exists as inactive protoxins in them. But, once an insect ingests it, it is converted into an active form of toxin due to the alkaline pH of the alimentary canal. The activated toxin binds to the surface of midgut epithelial cells and creates pores that cause swelling and lysis and finally cause the death of the insect.

Q84. Transgenic plants are the ones:

• A. Generated by introducing foreign DNA into a cell and regenerating a plant from that cell✓
• B. Produced after protoplast fusion in artificial medium
• C. Grown in artificial medium after hybridization in the field
• D. Produced by a somatic embryo in artificial medium

Explanation: The plants produced through genetic engineering contain genes, usually from an unrelated organism. Such genes are called transgenes and the plants having transgenes are called transgenic plants. Recombinant DNA techniques are being used to improve crop plants by increasing their productivity, making them more nutritious, and by developing disease resistance. Transgenic plants have a natural resistance to herbicides and pests. In the future, plants may have an ability to fix atmospheric nitrogen and an increased ability to grow in arid and salty soils.

Q85. What is true about the Bt toxin?

• A. Bt protein exists as active toxin in the Bacillus
• B. The activated toxin enters the ovaries of the pest to sterilise it and thus prevent its multiplication
• C. The concerned Bacillus has antitoxins
• D. The inactive protoxin gets converted into active form in the insect gut✓

Explanation: Soil bacterium Bacillus thuringiensis produces proteins that kill certain insects like lepidopterans (tobacco budworm, armyworm), coleopterans (beetles), and dipterans (flies, mosquitoes). B. thuringiensis forms some protein crystals which contain a toxic insecticidal protein. This toxin does not kill the Bacillus (bacterium) because it exists as inactive protoxins in them. But, once an insect ingests it, it is converted into an active form of toxin due to the alkaline pH of the alimentary canal. The activated toxin binds to the surface of midgut epithelial cells and creates pores that cause swelling and lysis and finally cause the death of the insect.

Q86. Any foreign substance often a protein which stimulates the formation of antibodies is called:

• A. Antigen✓
• B. Antibody
• C. Prion
• D. Virion

Explanation: The correct answer is 'Antigen'. Antigens are foreign substances, often proteins, that stimulate the immune system to produce antibodies to fight off potential threats. Antibodies, on the other hand, are proteins made by the immune system in response to antigens; they do not initiate the immune response. Prions and virions are infectious agents but do not directly stimulate antibody production as antigens do.

Q87. All antibodies of an individual are manufactured in:

• A. Alpha cells
• B. B-cells✓
• C. T-cells
• D. Delta cells

Explanation: B-cells recognize antigen and form plasma cell clone. These plasma cells synthesize and liberate antibodies into the blood plasma and tissue fluid.

Q88. Substance that can be recognized by the receptor of B-cells:

• A. Antigen✓
• B. Antibody
• C. Immunogen
• D. Food

Explanation: An antigen is a molecule that is recognized by the immune system, specifically by the receptors on B-cells, which triggers an immune response, including the production of antibodies. These can be proteins, polysaccharides, or other molecules from pathogens like bacteria and viruses.

Q89. In an antibody molecule two heavy chains and two light chains are bonded by:

• A. Disulphide bonds✓
• B. Hydrogen bonds
• C. Phosphodiester bonds
• D. Ionic bonds

Explanation: An antibody molecule consists of four polypeptide chains—two identical light chain and two identical heavy chains—linked by disulfide (-S—S-) bridges

Q90. What is the function of the cholesterol in a cell surface membrane?

• A. Controlling active transport
• B. Acting as a membrane blood receptor
• C. Helping cells join together
• D. Regulating the flexibility at the membrane✓

Explanation: Cholesterol helps to regulate membrane fluidity over the range of physiological temperatures. It has a hydroxyl group that interacts with the polar head groups of the membrane phospholipids and sphingolipids. Therefore, the correct answer is D.

Q91. Electron affinity decreases down the group due to:

• A. Increase in atomic radius✓
• B. Decrease in atomic radius
• C. Increase in electronegativity
• D. All of the above options are correct

Explanation: Electron affinity decreases from top to bottom within a group. This is caused by the increase in atomic radius.

Q92. If a molecule MX3 has zero dipole moment, the sigma bonding orbitals used by M are:

• A. Pure p
• B. sp hybrids
• C. sp2 hybrids✓
• D. sp3 hybrids

Explanation: In order for MX3 molecule to have zero dipole moment, it must have a symmetrical shape which in this case can only be trigonal planar. The bond angle in this case between X-X would be 120o so it should have sp2 hybrids.

Q93. Identify the correct statement:

• A. Element sodium can be prepared and isolated by electrolyzing an aqueous solution of NaCl
• B. Elemental Na is a strong oxidizing agent
• C. Elemental Na is insoluble in NH3
• D. Elemental Na is easily oxidized✓

Explanation: Good reducing agents include the active metals, such as sodium, magnesium, aluminum, and zinc, which have relatively small ionization energies and low electro-negativities.

Q94. The shape of sulphate ion is:

• A. Hexagonal
• B. Square planar
• C. Trigonal bipyramidal
• D. Tetrahedral✓

Explanation: d) Tetrahedral:The tetrahedral shape refers to a molecule with a central atom surrounded by four ligands, arranged at the corners of a tetrahedron. The sulfate ion (SO4^2-) has a tetrahedral shape since it has four oxygen atoms bonded to a central sulfur atom.

Q95. On the hydrogen atom spectrum, a series of spectral lines that fall within the visible region is:

• A. Lymen series
• B. Balmer Series✓
• C. Paschen series
• D. Bracket series
• E. Pfund series

Explanation: Lyman series of hydrogen atom lies in ultraviolet region, Balmer series lies in visible region while Pfund and Paschen series lie in infrared region.

Q96. How many chain isomer can be obtained from alkane C6H14 :

• A. 7
• B. 6
• C. 5✓
• D. 4

Explanation: Hexane (C6H14) has five possible isomers. The isomers are as follows;- Hexane, CH3CH2CH2CH2CH2CH3, a six carbon containing, saturated straight chain alkane. - 2-Methylpentane (Isohexane), CH3CH(CH3)CH2CH2CH3, which is a five carbon containing chain with one methyl branch on the carbon number 2.- 3-Methylpentane, CH3CH2CH(CH2)CH2CH3, is also a five-carbon chain, however the methyl group is attached on Carbon number 3.- 2,3-Dimethylbutane, CH3CH(CH3)CH(CH3)CH3, is a four-carbon -containing chain with a methyl group on carbon number 2 and 3.- 2,2-Dimethylbutane (neohexane), CH3C(CH3)2CH2CH3, is a four-carbon chain with two methyl groups attached on carbon number two.

Q97. The oxidation number of iodine is periodic acid (H5IO6) is:

• A. +7✓
• B. +3
• C. +6
• D. +5

Explanation: a) +7:The oxidation number of iodine in periodic acid (H5IO6) is indeed +7. In periodic acid, iodine is in its highest possible oxidation state. Each oxygen atom in the IO6 group carries an oxidation number of -2, and since the overall charge of the periodic acid molecule is 0, the oxidation number of iodine must be +7 to balance out the negative charges. Explanation:

Q98. The second and third period contain:

• A. 18 elements each
• B. 32 elements each
• C. 8 elements each✓
• D. 14 elements each

Explanation: Fact.The 2nd-period elements: lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, and neon. The 3rd-period elements: sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, and argon.

Q99. Which quantum number tells shape of the orbital?

• A. Magnetic quantum number
• B. Spin quantum number
• C. Azimuthal quantum number✓
• D. Principle quantum number

Explanation: The Azimuthal quantum number (l) describes the shape of the orbital.

Q100. The oxidation state of a free element is:

• A. 0✓
• B. >1
• C. -2
• D. -1

Explanation: The oxidation state of an atom in free or uncombined state is zero. For ions or molecular ions, the oxidation state is the net charge.

Q101. A carbonyl compound with molecular formula C5H10O reacted with iodine in an alkaline solution to give a pale yellow precipitate with an antiseptic smell.The carbonyl compound is:

• A. CH3CH2CH3CH3CHO
• B. CH3CH2CH2COCH3✓
• C. CH3CH2CH(CH3)CHO
• D. CH3CH2COCH2CH3

Explanation: b) CH3CH2CH2COCH3:This compound is 2-pentanone, which is a ketone with the molecular formula C5H10O. It is a likely candidate for the carbonyl compound in question. When reacted with iodine in an alkaline solution, it can form a pale yellow precipitate with an antiseptic smell.

Q102. Which class of the compounds is represented by the type formula ROR’?

• A. Esters
• B. Ethers✓
• C. Aldehydes
• D. Ketones

Explanation: A. "Esters" have the general formula R-COO-R'. B. "Ethers" have the general formula R-O-R' where R is the Alkyl group that is variant.C. "Aldehydes" have the general formula R-COH.D. "Ketones" have the general formula R-CO-R.

Q103. A piston in a cylinder is a part of?

• A. System
• B. Surroundings
• C. Boundary✓
• D. None of These

Explanation: The correct answer is Boundary. In thermochemistry, the piston in the cylinder serves as a boundary that separates the system from its surroundings. This boundary allows for changes in volume and work to be performed on or by the system without mixing the substances involved. The other options are incorrect as they misrepresent the role of the piston. The System refers to the actual substances involved in the reaction rather than a physical component like the piston. Surroundings refers to everything external to the system, while None of These is unfounded since the piston clearly has a defined role in thermodynamic terms.

Q104. Fossil fuels are produced due to _?

• A. Fast decomposition of organic matter.
• B. Decomposition of plants.
• C. Decomposition of animals.
• D. Biochemical decomposition of dead organic matter.✓

Explanation: Correct option is D. Fossil fuels are produced due to the biochemical decomposition of dead organic matter. Fossil fuels such as coal, oil, and natural gas are formed from the remains of plants and animals that lived millions of years ago. Over time, as these organic materials were buried under layers of sediment, they underwent a process called diagenesis, which involves the physical and chemical changes associated with the compaction and burial of the organic matter. This process, combined with high pressure and temperature over millions of years, led to the conversion of the organic material into fossil fuels. The biochemical decomposition of dead organic matter is the key process that creates fossil fuels, making them a non-renewable energy resource. d millions of years ago. They create carbon-rich deposits that are extracted and burned for energy. They are non-renewable and currently supply around 80% of the world's energy

Q105. The common name for 2-propanone is:

• A. Formaldehyde
• B. Acetone✓
• C. Benzaldehyde
• D. Acetaldehyde

Explanation: 2-Propanone is the systematic IUPAC name for the simplest ketone. Its widely used common name is acetone.

Q106. The current in electrolysis is carried through:

• A. Free electrons
• B. Positive ions
• C. Negative ions
• D. Both Options B and C are correct✓

Explanation: In electrolysis, current is carried through the electrolytic solution inside the cell by positive and negative ions using oxidation-reduction reactions. The liquid will continue to conduct electricity only as long as oxidation-reduction reactions occurring at the electrodes continue.

Q107. BH3 has a _ geometry with H-B-H bond angles of 120˚.

• A. Linear
• B. Trigonal planar✓
• C. Tetrahedron
• D. Bent

Explanation: If a molecule has 2 bond pairs and 0 lone pairs then the molecular shape will be linear. e.g. BeCl2If a molecule has 3 bond pairs and 0 lone pairs then the molecular shape will be trigonal planar. BH3 molecule has 3 bond pairs and 0 lone pairs with a bond angle of 120o . Therefore its geometry will be trigonal planar.Hence, B is the correct option.If a molecule has 4 bond pairs and 0 lone pairs then the molecular geometry will be tetrahedral. e.g. CH4If a molecule has 2 bond pairs and 2 lone pairs then they have bent geometry. e.g. H2O.

Q108. Element X is in group 3 and element Y is in group 6 of the periodic Table. Which of the following is the most likely formula of the compound formed when X and Y react together?

• A. X3Y2
• B. X3Y6
• C. X2Y3✓
• D. None of these

Explanation: Element X will have a valency of +3 while Y will have a valency of -2. Thus the most likely formula of the compound is X2Y3.

Q109. Addition of a second electron to a uni-negative ion is always _?

• A. An endothermic process✓
• B. An exothermic process
• C. Neutral process
• D. Energy wasted

Explanation: When a second electron is added to a uni-negative ion, the incoming electron is repelled by the already present negative charge, and energy is absorbed in this process. It is an endothermic process and the absorbed energy is given a positive sign. So, electron affinity is positive.O + e- → O1- EA1 = -141 kJ/molO- + e- → O2- EA2 = +744 kJ/mol.

Q110. Which compound is most ionic?

• A. Li2O
• B. MgO
• C. AlF3
• D. NaF✓

Explanation: Fluorine has a high negativity of 3.98, while Na has an electronegativity of Na is 0.93. For a compound to be ionic, the E.N difference must be greater than 2.1. 3.98 – 0.93 = 3.05 > 2.1, meaning that NaF is highly electronegative.

Q111. Which one of the following is not a secondary alkyl halide?

• A. 2-Chloropropane
• B. 3-Bromobutane
• C. 2,3-Dichloropentane
• D. 2-Chloro-2-methylpentane✓

Explanation: In this compound, the carbon atom bonded to chlorine is attached to only one other carbon atom (the methyl group). Therefore, it is not a secondary alkyl halide. Therefore, option d is correct.

Q112. The strength of London forces depends on the size of:

• A. Electrons.
• B. Electronic cloud.✓
• C. Lone pair on an atom
• D. Poles of atoms

Explanation: The strength of London forces depends upon the size of the electronic cloud of the atom or molecules. When the size of the atom or molecule is big then the dispersion becomes easy and these forces end up being more prominent.

Q113. Which class of halogenoalkane can react with alkali by an SN2 mechanism?

• A. Primary and secondary✓
• B. Secondary and tertiary
• C. Primary and tertiary
• D. Primary, secondary and tertiary

Explanation: a) Primary and secondary: This option suggests that both primary and secondary halogenoalkanes can react with alkali by an SN2 (substitution nucleophilic bimolecular) mechanism. In SN2 reactions, the nucleophile attacks the carbon atom bearing the leaving group, resulting in a simultaneous substitution of the leaving group and the nucleophile. Primary and secondary halogenoalkanes are suitable for SN2 reactions because they have a less hindered carbon center, allowing the nucleophile to approach and substitute the leaving group more easily.

Q114. The evaporation of water is an example of?

• A. Endothermic reaction✓
• B. Exothermic reaction
• C. Spontaneous reaction
• D. Chemical reaction

Explanation: Evaporation of water is an endothermic reaction. During evaporation, water molecules absorb heat from the surroundings and change into vapours and evaporate. That's why the surroundings become cool.

Q115. For which equilibrium does Kc has no unit?

• A. C(s) + H2O(g) -> CO(g) + 2H2(g)
• B. CH3OH(l) + CH3CO2H(l) -> CH2CO2CH2(l) + H2O(l)✓
• C. Cu2+(aq) + 4NH3(aq) -> Cu(NH3)42+(aq)
• D. N2O4(g) -> 2NO2(g)

Explanation: The equilibrium constant Kc is unitless when the total number of moles of gaseous or liquid reactants equals the total number of moles of gaseous or liquid products. In option B, the reaction involves only liquids with equal moles of reactants and products, so Kc has no unit. Option A involves a change in moles of gases, affecting Kc's units. Option C involves aqueous species with unequal moles of reactants and products, leading to units for Kc. Option D involves a difference in moles of gases, resulting in units for Kc.

Q116. Which of the following represents the equation for the reaction between ethane and chlorine in the presence of UV radiation?

• A. C2H4 + Cl2 -> C2H2Cl2 + H2
• B. C2H6 + Cl2 -> C2H5Cl + HCl✓
• C. C2H4 + Cl2 -> 2CH3Cl
• D. C2H4 + O2 -> 2CH2Cl + 2HCl

Explanation: Ethane reacts with chlorine by free radical halogenation in the presence of In the presence of sunlight, Cl2 breaks down (homolytically) to form two chlorine radicals. This is the initiation step. I will use the * symbol to indicate a radical, in fact this should be expressed using a superscript dot.Cl2 => The generated chlorine radical can then react with ethane to give an ethane radical (C2H5*) and HCl.C2H6 + Cl* => C2H5* + HClThe ethane radical then reacts with another molecule of chlorine to generate the initial halogenated product and another chlorine radical which can react again. This is the propagation step.C2H5* + Cl2 => C2H5Cl + Cl*The newly generated chlorine radical can now either react with another molecule of ethane (as above) or react with the halogenated product to give further halogenated products:C2H5Cl + Cl* => C2H4Cl2

Q117. If temperature of reaction medium increases above optimum temperature then _ ?

• A. It increases the enzyme activity
• B. Stops the reaction
• C. Decreases the enzyme activity
• D. Both b and c✓

Explanation: At optimum temperature enzymes have maximum activity, if the temperature increases further their activity decreases and at very high temperatures the enzymes will be denatured due to permanent deformation of the active sites and all activity will stop.

Q118. Which of the following gives a free radical reaction when it reacts with alkanes?

• A. Nitric acid
• B. Oxygen
• C. Halogen✓
• D. All of these options are correct

Explanation: When halogens react with alkanes, the reaction is a free radical reaction. The reaction involves three steps: initiation, propagation, and termination.

Q119. The number of electrons in the p subshell is:

• A. 2
• B. 14
• C. 10
• D. 6✓

Explanation: p subshell has 3 orbit and 1 orbit has maximum 2 electrons.

Q120. The number of nitrogen atoms present in 160 amu of ammonium nitrate are:

• A. 4✓
• B. 5
• C. 6
• D. 8

Explanation: 1 molecule of NH4NO3 = 80 amuAs 2 times 80 is 160, therefore by balanced chemical equation, 160 amu of NH4 are present in two molecules.80 amu : 1 molecule80 × 2 amu : 2 molecules160 amu : 2 molecules

Q121. Carboxylic acids are produced by the oxidation of _?

• A. Alcohol
• B. Aldehyde
• C. Ketone
• D. All of these✓

Explanation: All of the above can oxidise and form carboxylic acids.

Q122. The net enthalpy change in a chemical reaction is same whether it is brought about in two or more different ways in one or several steps. It is known as:

• A. Joule’s law
• B. Law of conservation of energy
• C. Hess’s law✓
• D. Henry's law

Explanation: According to Hess's law, the thermal effects of a reaction depends upon the initial and final conditions of the reacting substances. It does not depend upon the immediate steps.

Q123. Which increases down the group for alkali metals?

• A. Electron affinity
• B. Reactivity✓
• C. Ionisation energy
• D. All of the above options are correct

Explanation: The reactivity of Group I elements increases as you go down the group because: the atoms get larger as you go down the group. the outer electron gets further from the nucleus as you go down the group.

Q124. Which one of the following has highest bond energy?

• A. HI
• B. HCL
• C. HF✓
• D. HBr

Explanation: HF has the highest bond energy since fluorine is the most electronegative halogen and would bind strongly with an electropositive hydrogen. Therefore the highest bond energy would be of HF.

Q125. Oxidation of a primary alcohol with PCC (Pyridiniumchlorochromate) gives a/an:

• A. Aldehyde✓
• B. Ketone
• C. Carboxylic acid
• D. Ester

Explanation: PCC is a mild oxidizing agent that is selective for the oxidation of primary alcohols. It converts them to aldehydes and is not strong enough to oxidize them further to carboxylic acids.

Q126. It is impossible for two electrons to have same value of spin quantum number in the same orbital, according to:

• A. Hund’s rule
• B. Aufbau principle
• C. Pauli’s exclusion principle✓
• D. All of the above options are correct

Explanation: The Pauli Exclusion Principle states that, in an atom or molecule, no two electrons can have the same four electronic quantum numbers. As an orbital can contain a maximum of only two electrons, the two electrons must have opposing spins.

Q127. Nature of diamond as solid is:

• A. Covalent✓
• B. Ionic
• C. Molecular
• D. Metallic

Explanation: It has a single type of atom and we have discussed above that among similar atoms covalent bonding is seen. Therefore, we can say that the nature of bond in diamonds is covalent.

Q128. How many moles of CO2 contain 16g of oxygen?

• A. 5 mol
• B. 16 mol
• C. 0.5 mol✓
• D. 2 mol

Explanation: 1 mol of CO2 contains = 32 g O2=1 6 g O2 will be present in = 16/32 = 0.5 mol

Q129. Point out the property which is not characteristic of alkali metal:

• A. Low electronegativity
• B. Low melting point
• C. Their ions are isoelectronic with noble gas
• D. High ionization energy✓

Explanation: Alkali metals have low ionization energies due to their larger atomic radii.

Q130. Which contains sp2 hybridization?

• A. Methane
• B. Ethane
• C. Alkyne
• D. None of these options are correct✓

Explanation: The hybridization of methane molecules occurs by mixing one orbital with three p orbitals. In ethane (CH3CH3), both carbons are sp3-hybridised. Alkynes undergo sp hybridization.

Q131. Homocyclic hydrocarbons are further divided into:

• A. Alicyclic and aromatic✓
• B. Carbocyclic and heterocyclic
• C. Acyclic and heterocyclic
• D. Heterocyclic and aromatic

Explanation: Homocyclic compounds are divided into two compounds. Alicyclic compounds and aromatic compounds.

Q132. Example of a nucleophile is:

• A. BF3
• B. AlCl3
• C. SO3
• D. CN✓

Explanation: A nucleophile is a species that donates a pair of electrons to form a covalent bond. Examples of nucleophiles include negatively charged ions (such as CN-, OH-, and NH2-) and neutral molecules with a lone pair of electrons (such as H2O, NH3, and CH3OH). In this case, CN- is a nucleophile.

Q133. Diameter of an atom is in the range of?

• A. 0.2m
• B. 0.2 nm✓
• C. 2 x 10-19nm
• D. 0.2 pm

Explanation: The diameter of an atom is 0.2nm. PTB-Pg 2

Q134. Magnesiums keep on burning in:

• A. CO2
• B. Magnesium and Copper
• C. N2O
• D. N2 as well as CO2✓

Explanation: When burning magnesium is placed in carbon dioxide it keeps burning with a bright flame. it burns in N2 aswell.

Q135. Instantaneous acceleration of system executing SHM is directed:

• A. Towards the mean position✓
• B. Away from the mean position
• C. Perpendicular to the mean position upward
• D. Perpendicular to the mean position downward

Explanation: As the acceleration in SHM is always in the opposite phase to that of displacement. The displacement of the particle in SHM at an instant is directed away from the mean position. Then acceleration at that instant is directed towards the mean position.

Q136. A wire of initial length L and radius r is stretched by a length I. Another wire of the same material but with an initial length of 2L and radius 2r is stretched by length 2l. The ratio of the stored elastic energy per unit volume in the first and second wire is:

• A. 1:4
• B. 1:2
• C. 2:1
• D. 1:1✓

Explanation: This is the following solution:

Q137. In rotatory motion, angular momentum plays a role which is analogous to that played by _ in linear motion.

• A. Linear velocity
• B. Linear momentum✓
• C. Linear acceleration
• D. Inertia

Explanation: The rotational momentum and "linear momentum both form the same function in a body, they are responsible for keeping the body moving in the direction it is moving, and both quantity the amount of motion (translational tor linear momentum and rotational tor angular momentum) present in the body. Moment of inertia in an analogue to mass in rotational motion. If we want to feel inertia in linear motion we examine the linear acceleration of mass produced by a given force. If acceleration for a given force is more we say that the body has less inertia. If the same force produces less acceleration in another mass then the inertia of the second body for linear motion is large compared to the first body. The expression for this fact is F/m=a. So, mass is the measure of inertia to linear motion.

Q138. The velocity of a car traveling on a straight road is 36 km/h at an instant of time. Now traveling with uniform acceleration for 10s. The velocity becomes exactly double if the wheel radius of the car is 25cm then which of the following numbers is the closest to the number of revolutions that the wheel makes during these 10s?

• A. 84
• B. 95✓
• C. 126
• D. 135

Explanation: This is the following question:

Q139. Relationship between angular and linear velocity is:

• A. ω= rv
• B. v= rω✓
• C. ω= v/r2
• D. v= ω/r

Explanation: Relation Between Linear Velocity and Angular Velocity |v| = rω, which is the relation between linear and angular velocity.

Q140. A man throws a ball vertically upward in the compartment of an accelerated train. The ball will fall:

• A. ln front of him
• B. In his hand
• C. Behind him✓
• D. Beside him

Explanation: At the time of throwing the ball, it inherits velocity of platform at that moment . And, the horizontal velocity of the ball is constant in the air, because no acceleration in horizontal direction for ball. However, the train is accelerating in forward direction then from frame of train, the ball has horizontal component of acceleration in backward direction.

Q141. projectile motion, the range of projectile will be maximum at an angle of:

• A. 30 degrees
• B. 45 degrees✓
• C. 80 degrees
• D. 90 degrees

Explanation: The greatest the value of sin of anything can be is 1. This angle will be at 45 degrees.

Q142. The average translational kinetic energy for molecule of an ideal gas is given by:

• A. Option A✓
• B. Option B
• C. Option C
• D. Option D

Explanation: The average translational kinetic energy of a molecule in an ideal gas is given by the formula 3/2R/NAT, where is the Boltzmann constant and is the absolute temperature. This formula is derived from the equipartition theorem, which assigns of energy per degree of freedom. An ideal gas molecule has three translational degrees of freedom, thus the total translational kinetic energy is . The other options either represent incorrect applications of the equipartition theorem or miscalculate the energy distribution across degrees of freedom.

Q143. Which of the following statement is incorrect:

• A. Photoelectric emission does not occur below the threshold frequency
• B. The photoelectric current increases with the frequency of incident light✓
• C. Threshold frequency depends on the metal used
• D. The emission of photoelectrons is an instantaneous process

Explanation: In photoelectric effect Electrons are emitted instantaneously; the intensity of light determines only their numbers. So, photoelectric current is independent on the frequency of light.

Q144. What is the internal energy of an object?

• A. It is the energy associated with the object's movement through space.
• B. It is the sum of all the microscopic potential and kinetic energies of the molecules✓
• C. It is the energy due to attractions between the molecules within the object.
• D. It is the energy associated with the random movement of the molecules in the object.

Explanation: Internal energy includes energy on a microscopic scale. It is the sum of all the microscopic energies such as: translational kinetic energy, vibrational and rotational kinetic energy, and potential energy from intermolecular forces.

Q145. Which of the following is not true?

• A. Momentum is quantity of motion
• B. Unit of momentum is N.s
• C. Momentum is not a vector quantity✓
• D. Momentum is product of mass and velocity

Explanation: Momentum is a vector quantity. The direction of an object's momentum vector is in the direction that the object is moving.

Q146. The range of the projectile when launched at an angle of 15 degrees with the horizontal is 15 m. Its range, when launched at 45 degrees with the same speed is:

• A. 30.0 m✓
• B. 1.5 m
• C. 6.0 km
• D. 0.752 km

Explanation: The range of a projectile is given by the formula R = (v0² sin(2θ)) / g, where v0 is the initial speed, θ is the launch angle, and g is the acceleration due to gravity. When θ = 15 degrees, R = 15 m. When the angle is increased to 45 degrees, the formula predicts that the range doubles, as sin(90 degrees) = 1, which maximizes the formula. Therefore, the range is 30 m. The other options provide ranges that are either too small or unrealistic, not aligning with basic projectile motion principles.

Q147. A ball is thrown vertically upward with a velocity of 98 m/s. if it takes 10 seconds to reach the highest point then the acceleration of the ball is:

• A. 9.8 m/s²
• B. 980 m/s
• C. 98 m/s²
• D. -9.8 m/s✓

Explanation: Using the first equation of motion: v = u + at final velocity(v) =0m/s initial velocity (u) =98m/s time (t) = 10 acceleration (a) = ? 0=98+10a -98=10a a=-9.8m/s²

Q148. Alpha rays are nuclear radiation. They are the same as the _ nuclei.

• A. Hydrogen
• B. Deuterium
• C. Tritium
• D. Helium✓
• E. Lithium

Explanation: Alpha particle has charge of +2e and mass no 4Hydrogen has a charge of +e and mass no 1Deutrium has charge of +e and mass no 2Tritrium has charge of +e and mass no 3Helium has charge of +2e and mass no 4 Lithium has charge of +3e and mass no 7This confirms that alpha rays are same as the Helium Nuclei.

Q149. A magnetic needle is placed in a uniform magnetic field and is aligned with the field. The needle is now rotated by an angle of 60 degrees and work done is W. The torque on the magnetic needle at this position is

• A. 2√3 W
• B. √3 W✓
• C. √(3/2) W
• D. √(3/4) W

Explanation: The torque (τ) on a magnetic needle in a uniform magnetic field is given by the formula τ = mB sin(θ), where m is the magnetic moment, B is the magnetic field strength, and θ is the angle between the magnetic moment and the magnetic field. In this case, the needle is rotated by 60 degrees, so sin(60°) = √3/2. Therefore, the torque can be expressed in relation to the work done (W) when the needle aligns with the magnetic field. Since the work done is given as W, at 60 degrees, the correct torque value simplifies to √3 W. The other options are incorrect because they either miscalculate the sine value for the given angle or do not follow the relationship between torque and work accurately.

Q150. When two bodies move towards each other with constant speed, the distance between them decreases at the rate 6m/sec. If they move in the same direction, the distance between them increases at the rate of 4 m/sec. Calculate their velocities.

• A. 5 m/sec, 1 m/sec✓
• B. 3 m/sec, 3 m/sec
• C. 6 m/sec, 1 m/sec
• D. 4 m/sec, 2 m/sec

Explanation: Let's name the two unknown speeds as V1 and V2.From the information given,V1+V2 = 6V1 - V2 = 4Solving the equations simultaneously,V1 = 4 + V2Substituiting this in first equation,4 + V2 + V2 = 6 2V2 = 2V2 = 1 m/sV1 = 4 + V2 V1 = 4 + 1V1 = 5 m/s.Option A is the correct answer.

Q151. A bar magnet has a magnetic moment 200 Am2. The magnet is suspended in a magnetic field of 0.30 NA-1m-1. The torque required to rotate the magnet from its equilibrium position at an angle of 30˚ will be:

• A. 30Nm✓
• B. 3073 Nm
• C. 60Nm
• D. 604Nm

Explanation: τ = MBsinθTorque = 200×0.30×sin30 = 30 Nm.

Q152. Two capacitors C1 (6µF) and C2 (12µF) are in series across a 180 volts D.C supply. Calculate the charges on C1 and C2 respectively.

• A. 120x106 C, -420x106 C
• B. 320x10-6 C, 420x10-6 C
• C. 420x10-6 C, 320x10-6 C
• D. 720x10-6 C, 720x10-6 C✓
• E. 620x10-6 C, 420x10-6 C

Explanation: Charge remains same in series and charges of both capacitors are only same in Option D and so it is the right answer.You can even calculate the charge using this;net capacitance in series:1/C= 1/C1 + 1/C21/C = 1/12 + 1/6 C= 4x10-6 FC=Q/V4x10-6 = Q/180Q= 720 x 10-6 C

Q153. In perfect elastic collision

• A. Only momentum is conserved
• B. Only total energy is conserved
• C. Only kinetic energy is conserved
• D. Momentum, kinetic energy, and total energy is conserved✓

Explanation: Kinetic energy and hence momentum is conserved only in elastic collision. The kinetic energy is not conserved in inelastic collisions but the total energy is conserved in all types of collisions.

Q154. Find the resistance if voltage of the circuit is 45 volts and current 30 Amp.

• A. 1.6 ohm
• B. 1.5 ohm✓
• C. 1.7 ohm
• D. 1.8 ohm

Explanation: R = V / ISubstituting the given values, we get:R = 45 V / 30 A = 1.5 ohmTherefore, the resistance of the circuit is 1.5 ohm

Q155. If the mass of the bob of simple pendulum is doubled, its time period is:

• A. One half
• B. Doubled
• C. Remains constant✓
• D. One fourth

Explanation: Time period of a simple pendulum is given by T=1/2π √ (l/g). This means that the time period of a pendulum does not depend on the mass of the bob. So, if the mass of the bob doubled, the time period remains the same.

Q156. A boy standing in a lift falling freely under gravity releases a ball from his hand. As seen by him the ball:

• A. Falls down
• B. Remains stationary✓
• C. Goes up
• D. None of the above

Explanation: The correct option is B) Remain stationaryWhen the lift falls freely under gravity (in free fall), everything inside the lift, including the boy and the ball, accelerates at the same rate due to gravity. Since both the boy and the ball are accelerating downward at the same rate, they effectively remain in the same relative position within the lift. Therefore, as observed by the boy, the ball would appear to remain stationary in the air when released from his hand. Gravity is acting equally on both the boy and the ball, causing them to fall together, and the ball does not exhibit any relative motion with respect to the boy in this scenario.

Q157. Two stones, 10kg and 50kg fall through 80m high cliff. Which stone has greater velocity at bottom? (ignoring air resistance)(g=10ms-2)

• A. 10kg
• B. 50kg
• C. Both have same velocity✓
• D. Cannot be calculated

Explanation: If we neglect air resistance both objects reach the ground at the same time so their velocity will be the same.

Q158. A motorist travelling at 10 ms^-1 can bring his car to rest in a braking distance of 10 m. In what distance could he bring the car to rest from the period of 30 ms^-1 using the same breaking force?

• A. 17 m
• B. 30 m
• C. 52 m
• D. 90 m✓

Explanation: To solve this problem, use the equation of motion: 2as = v² - u².First, determine the acceleration when the initial velocity is 10 m/s and the car stops (v = 0 m/s) over 10 m:2(a)(10) = 0² - 10²20a = -100a = -5 m/s²Next, use the same acceleration for the initial velocity of 30 m/s:2(-5)(s) = 0² - 30²-10s = -900s = 90 mThis calculation shows that the car will take 90 meters to stop from 30 m/s with the same braking force. The other options are incorrect due to miscalculations or misunderstandings of the relationship between velocity and stopping distance.

Q159. The time rate of change of velocity is called:

• A. Force
• B. Acceleration✓
• C. Power
• D. Energy

Explanation: Acceleration is defined as the rate of change of velocity with respect to time. Acceleration is a vector quantity, so it includes both magnitude and direction.

Q160. The path difference for the constructive interference is:

• A. (n-1)λ
• B. (n+1)λ
• C. n λ / 2
• D. 2n λ
• E. n λ✓

Explanation: Option A: (n-1)λ: This is the path difference for destructive interference. When the path difference is one wavelength less than a whole number of wavelengths, the waves will be out of phase and will cancel each other out. Option B: (n+1)λ: This is also the path difference for destructive interference. When the path difference is one wavelength more than a whole number of wavelengths, the waves will be out of phase and will cancel each other out. Option C: nλ/2: This is the path difference for a node. A node is a point where the waves cancel each other out completely. Option D: 2nλ: This is not possible, as the path difference cannot be greater than the wavelength of the wave. Option E: The path difference for constructive interference is nλ, where n is any integer. This means that the difference in the distance traveled by two waves must be a whole number of wavelengths. When this happens, the waves will be in phase and will add together to create a larger wave.

Q161. Conversion of heat energy completely into work violates:

• A. Zeroth law of thermodynamics
• B. First law of thermodynamics
• C. Second law of thermodynamics✓
• D. Both, the first and second laws of thermodynamics

Explanation: Conversion of heat energy completely into work implies no loss of energy. Second law of thermodyanmics states that not all heat energy can be converted into work in a cyclic process. Therefore, this statement is exactly oopposite to second law of thermodynamics.

Q162. If an ideal gas has volume V at 27°C and it is heated at constant pressure so that it volume become 1.5V, the value of final temperature is:

• A. 327K
• B. 871K
• C. 177°C✓
• D. 600°C

Explanation: According to Charles Law, V1/T1 = V2/T2(Note: For these questions, always make sure the temperature is in Kelvin)Initial temperature = 27°C For converting temperature in Celcius to Kelvin:273+27 = 300KV/300 = 1.5V/T2T2= (1.5V x 300)/VT2=450KFor converting temperature in Kelvin to Celcius:450-273 = 177°C

Q163. The slope of displacement-time graph is:

• A. Velocity✓
• B. Displacement
• C. Acceleration
• D. Distance

Explanation: The slope of the displacement-time graph gives the velocity of an object while the slope of the distance-time graph gives the speed of an object.

Q164. A wire carries a current out of the page. Which diagram below correctly describes the magnetic field of the wire?

• A. Option A
• B. Option B
• C. Option C
• D. Option D✓
• E. Option E

Explanation: The magnetic field lines form concentric circles around the wire. If you wrap your right hand’s fingers around the wire with your thumb pointing in the direction of the current, then the direction in which the fingers curl will give the direction of the magnetic field. As the current is directed out of the page, then the magnetic field will have a counter clockwise direction. So “D” is the correct answer.

Q165. An electric cell of e.m.f E, is connected across a copper wire of diameter d and length L. The drift velocity of electrons in the wire is v0. If the length of the wire is changed to 2L, the new drift velocity of electrons in the copper wire will be:

• A. V
• B. 2V
• C. V/2✓
• D. V/4

Explanation: At constant voltage, the drift velocity is inversely proportional to the length of the conductor. So If the length of the conductor is doubled, the drift velocity will become half of the original value.

Q166. An alpha particle is ejected from the nucleus of an atom. Which of the following answers describes the change in the nucleus of the atom?

• A. The atomic number increases by 1, and the mass number remains unchanged.
• B. The atomic number increases by 1, and the mass number decreases by 4.
• C. The atomic number increases by 1, and the mass number increases by 2.
• D. The atomic number increases by 2, and the mass number increases by 4.
• E. The atomic number decreases by 2, and the mass number decreases by 4.✓

Explanation: Alpha emission decreases mass number by 4 and atomic number by 2 for each emitted alpha particle. Gamma emission has no effect on the parent atom. Beta emission causes an increase of proton number by 1.

Q167. A frictional piston-cylinder based enclosure contains some amount of gas at a pressure of 400k Pa. Then heat is pressure in a quasi-static process. The piston moves up slowly through a height of 10cm. lf the piston has across section area of 0.3m2,the work done by the gas in the process is:

• A. 6kj
• B. 12kj✓
• C. 75kj
• D. 24kj

Explanation: This is the following solution:

Q168. A force F = 0.12 N is applied to a spring and the spring elongates by 3 cm. The specific constant of the spring is?

• A. 0.4 Nm-2
• B. 40 Nm-1
• C. 400 Nm-1
• D. 4 Nm-1✓

Explanation: When a spring is stretched/compressed by the application of a force, the relationship between the magnitude of the force applied and the elongation of the spring is given by Hooke's law: F=kx Where F is the magnitude of the spring applied k is the spring constant x is the elongation of the spring relative to its equilibrium position For the spring in this problem, we have: F = 0.12 N (force applied) x = 3 cm = 0.03 m (elongation of the spring) Therefore, we can solve the formula for k to find the spring constant: k=F/x k= 0.12/0.03 k= "4N/m"

Q169. In a ripple tank 100 waves pass through a certain point in one second. If the wavelength of the wave is 1cm then the speed of the wave will be?

• A. 1 ms-1✓
• B. 2 ms-1
• C. 3 ms-1
• D. 4 ms-1

Explanation: Frequency=100, Wavelength= 1cm = 1/100 = 0.01m.Frequency = Speed/Wavelength(Frequency) (Wavelength) =Speed(100)(0.01)=1m/s.

Q170. The light exhibits the phenomena of constructive interference under the situation when it is _ and _.

• A. Monochromatic and in Phase✓
• B. Monochromatic and out of Phase
• C. In phase and non-monochromatic
• D. Out of phase and non-monochromatic

Explanation: Option A: The light exhibits the phenomena of constructive interference under the situation when it is monochromatic and in phase. Monochromatic light means that the light waves have a single wavelength. This is important because constructive interference can only occur if the waves are in phase with each other. When two waves are in phase, they have the same amplitude and the same wavelength. This means that when they overlap, they add together to create a larger wave. Option B: Monochromatic and out of phase: This will not produce constructive interference. Out of phase waves have different amplitudes and/or different wavelengths. When out of phase waves overlap, they cancel each other out. Option C: In phase and non-monochromatic: This will not produce constructive interference. Non-monochromatic light means that the light waves have multiple wavelengths. The different wavelengths of the light will not be in phase with each other, and they will cancel each other out. Option D: Out of phase and non-monochromatic: This will not produce constructive interference. Out of phase waves have different amplitudes and/or different wavelengths. When out of phase waves overlap, they cancel each other out.

Q171. 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.

Q172. 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

Q173. Children go to school because:

• A. They want to learn poems.
• B. They want to be away from home.
• C. They want to look beautiful.
• D. They want to gain knowledge.✓
• E. They want to tease the teacher.

Explanation: The question is asking for the purpose of schooling.

Q174. 3, 6, 18, 72, _

• A. 144
• B. 216
• C. 288
• D. 360✓

Explanation: The sequence follows a pattern where each number is obtained by multiplying the previous number by successive integers. This means:3 multiplied by 2 equals 66 multiplied by 3 equals 1818 multiplied by 4 equals 72To find the next number in the sequence, you multiply 72 by 5, resulting in 360. Therefore, 360 is the correct answer. The other options do not follow this pattern of sequentially increasing multipliers.

Q175. If 7(x-2) = 3x - 2. What is the value of x?

• A. -4
• B. -3
• C. 2
• D. 3✓
• E. 4

Explanation: To solve the equation 7(x-2) = 3x - 2, begin by expanding the left side: 7x - 14 = 3x - 2. Next, move all terms involving x to one side and constant terms to the other: 7x - 3x = -2 + 14. Simplify to get 4x = 12. Divide both sides by 4 to find x = 3.Options A, B, C, and E result in incorrect equations when substituted back into the original equation, hence they are incorrect.

Q176. 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

Q177. Passage: There is a family of six persons G, J, B, E, T and Z. Their professions are teacher, writer, actor, singer, dancer and lawyer but not respectively in the same order. G is a teacher. Z is a dancer. B is neither writer nor actor. E is neither singer nor lawyer. T is an actor. J is a lawyer. Who among them has a profession of lawyer?

• A. J✓
• B. B
• C. E
• D. T

Explanation: The passage explicitly states, "J is a lawyer." Therefore, J is the person with the profession of a lawyer.

Q178. Passage: There is a family of six persons G, J, B, E, T and Z. Their professions are teacher, writer, actor, singer, dancer and lawyer but not respectively in the same order. G is a teacher. Z is a dancer. B is neither writer nor actor. E is neither singer nor lawyer. T is an actor. J is a lawyer. Who among them has a profession of lawyer?

• A. J✓
• B. B
• C. E
• D. T

Explanation: The passage explicitly states, "J is a lawyer." Therefore, J is the person with the profession of a lawyer.

Q179. Each problem consists of three statements. Based on the first two statements, the third statement may be true, false, or uncertain.Blueberries cost more than strawberries.Blueberries cost less than raspberries.Raspberries cost more than both strawberries and blueberries.If the first two statements are true, the third statement is:

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

Explanation: The first two statements provide a clear hierarchy of fruit prices: blueberries are more expensive than strawberries, and raspberries are more expensive than blueberries. Therefore, raspberries must be more expensive than both strawberries and blueberries, making the third statement true. Option A is correct as it accurately reflects this deduction. Options B and C are incorrect because the cost relationships provided lead to a definite conclusion about the third statement. Option D is also incorrect as it suggests there is no correct option, which contradicts the evidence given.