Uhs Mdcat 2013 — Solved Past Paper with Answers

Q1. Indolence gives vent to _ disposition in human life.

• A. Static✓
• B. Enthusiastic
• C. Energetic
• D. Filthy

Explanation: Indolence refers to laziness or a lack of motivation or effort. When a person is indolent, they tend to be inactive or lethargic, resulting in a static disposition.

Q2. The Quaid’s _ enthusiasm led the Muslims of Indo-Pak to independence.

• A. Simplified
• B. Latent
• C. Onerous✓
• D. Threatening

Explanation: Onerous means involving a great amount of effort, difficulty, or responsibility. "Onerous" suggests that Quaid's enthusiasm was characterized by a significant and challenging burden, indicating the determination and hard work required to achieve independence.

Q3. He _ the incident to the back of his mind.

• A. Revered
• B. Regulated
• C. Reagitated
• D. Relegated✓

Explanation: Relegated means to degrade or devalue something, in this case the incident, which he did by putting it at the back of his mind.

Q4. He _ the day they had bought such a large house.

• A. Hues
• B. Rows
• C. Rues✓
• D. Dues

Explanation: Rue is the most applicable word over here as he might be having some problem due to buying such a large house. Rues means to feel regret, remorse, or sorrow for something.

Q5. Identify the incorrect segment: Amjad was not conscious to the aberration he had committed in the public meeting. It was disliked by all and sundry.

• A. to✓
• B. the
• C. in
• D. by

Explanation: The correct phrase should be "conscious of" instead of "conscious to". Therefore, the sentence should be: "Amjad was not conscious of the aberration he had committed in the public meeting."

Q6. Identify the incorrect segment: Late Agha Shahi was an outstanding genius in the international affairs. He was gifted of the acumen to judge the future events, judge the future events in advance.

• A. in
• B. of✓
• C. to
• D. in

Explanation: The correct phrase should be "gifted with" instead of "gifted of." Therefore, the sentence should be: "He was gifted with the acumen to judge the future events in advance."

Q7. Identify the incorrect segment: The old man was sitting quite bamboozled when the swindler deprived him from his pension money by his evil tricks.

• A. Quite
• B. From✓
• C. By
• D. His

Explanation: The correct preposition to use in this context is 'of' instead of 'from'. Therefore, the sentence should be: "The old man was sitting quite bamboozled when the swindler deprived him of his pension money by his evil tricks."

Q8. Identify the incorrect segment: The prime minister fired a broadside at the opposition leaders. A few of his remarks were not up at the mark.

• A. of
• B. were
• C. up
• D. at✓

Explanation: The correct phrase should be "upto" instead of "up at." Therefore, the sentence should be: "The prime minister fired a broadside at the opposition leaders. A few of his remarks were not up to the mark." The phrase "up to the mark" is a common idiom meaning meeting the expected standard or level of quality.

Q9. Identify the incorrect segment: Lucy is the diva which performance as an opera singer is peerless.

• A. which✓
• B. as
• C. an
• D. peerless

Explanation: The correct relative pronoun to use in this context is "whose" instead of "which." Therefore, the sentence should be: "Lucy is the diva whose performance as an opera singer is peerless." The relative pronoun "whose" is used to indicate possession or association, whereas "which" is used to provide additional information about a non-human object. Since Lucy is a person in this sentence, "whose" should be used to indicate possession of the performance as an opera singer.

Q10. Identify the incorrect segment: The police report excused Anwar of all charges of corruption and job was also restored.

• A. excused✓
• B. of
• C. also
• D. restored

Explanation: The answer is A, as the appropriate word to use here would have been exonerated. The word "exonerated" means to clear someone of blame or responsibility, especially in a legal or official context. "Excused" implies pardoning or forgiving someone, which does not convey the intended meaning of clearing someone of charges.

Q11. Choose the correct sentence from the following:

• A. We should pay maximum accolade for our national heroes
• B. We should pay maximum accolade in our national heroes
• C. We should pay maximum accolade to our national heroes✓
• D. We should pay maximum accolade from our national heroes

Explanation: The preposition "to" is commonly used with the word "accolade." Therefore, the correct sentence is: "We should pay maximum accolade to our national heroes."

Q12. Choose the correct sentence from the following:

• A. The Return of the King which is a popular movie made a huge amount of money
• B. "The Return of the King", which is a popular movie made a huge amount of money.
• C. "The Return of the King", which is a popular movie, made a huge amount of money.✓
• D. "The return of the king", which is a popular, movie, made a huge amount of money.

Explanation: The Return of the King is a title, therefore it must be in between quotation marks. Therefore, Option A is incorrect. Since it is a title, it must also be capitalised. This means that option D is incorrect.Finally, 'which is a popular movie' is a dependent clause. Therefore, it must be contained within commas. This means option B is incorrect. Therefore, option C is the right answer.

Q13. Select the NEAREST CORRECT MEANING of the given word: HEINOUS

• A. Heroic
• B. Humorous
• C. Odious✓
• D. Hone

Explanation: Heinous means (wrongful act, especially a crime) utterly odious or wicked.

Q14. Select the NEAREST CORRECT MEANING of the given word: ILLICIT

• A. Intimate
• B. Licentious
• C. Illegal✓
• D. Limited

Explanation: Illicit means forbidden by the law. "Illegal" means not permitted by law or contrary to legal regulations. It is the correct and nearest meaning to "Illicit."

Q15. Select the NEAREST CORRECT MEANING of the given word: MOTIF

• A. Tough
• B. Stuff
• C. Motion
• D. Design✓

Explanation: Motif is a decorative image or design, especially a repeated one forming a pattern. "Design" refers to a pattern, theme, or recurring element used in art, literature, or music. It is the correct and nearest meaning to "motif."

Q16. Select the NEAREST CORRECT MEANING of the given word: INCULCATE

• A. Calculate
• B. Instill✓
• C. Instigate
• D. Stimulate

Explanation: "Inculcate" is to teach (someone) an attitude, idea, or habit by persistent instruction and ingrain it in them. "Instill" is to gradually but firmly establish (an idea or attitude) in a person's mind.

Q17. Select the NEAREST CORRECT MEANING of the given word: INIQUITY

• A. Inequality
• B. Injustice
• C. Wickedness✓
• D. Efficiency

Explanation: Iniquity means immoral or grossly unfair behavior. "Wickedness" refers to behavior or actions that are morally wrong, evil, or sinful. It is the correct and nearest meaning to "Iniquity."

Q18. Select the NEAREST CORRECT MEANING of the given word: INTRANSIGENT

• A. Parallel
• B. Inflexible✓
• C. Adventurous
• D. Spirited

Explanation: Intransigent is to be uncompromising, unwilling, or refusing to change one's views or to agree about something. "Inflexible" means refusing to change or compromise, stubborn, or uncompromising. It is the correct and nearest meaning to "Intransigent."

Q19. Select the NEAREST CORRECT MEANING of the given word: LAMPOON

• A. Irk
• B. Gratification
• C. Lacerate
• D. Ridicule✓

Explanation: Lampoon means to publicly criticize, mock (someone or something) by using ridicule, irony, or sarcasm.

Q20. Select the NEAREST CORRECT MEANING of the given word: MESMERIZE

• A. Objectifiy
• B. Modify
• C. Amalgamate
• D. Fascinate✓

Explanation: Mesmerise means to transfix someone and get their complete attention. It is synonymous with fascination.

Q21. Select the NEAREST CORRECT MEANING of the given word: OBLITERATE

• A. Sanctify
• B. Obscure
• C. Annihilate✓
• D. Oplate

Explanation: Obliterate means to utterly destroy or wipe out. Annihilate means to destroy completely, wipe out, or eradicate something. It is the correct and nearest meaning to "obliterate."

Q22. Select the NEAREST CORRECT MEANING of the given word: MALEVOLENCE

• A. Empthay
• B. Maligning
• C. Hostility✓
• D. Management

Explanation: Malevolence is being spiteful. Hostility refers to a state of antagonism, animosity, or unfriendliness. It is the correct and nearest meaning to "malevolence."

Q23. The simplest independent unit of life is known as:

• A. Bacterial colony
• B. Cell✓
• C. Chloroplast
• D. DNA

Explanation: The cell is the simplest entity that can exist as an independent unit of life. Every known living organism is either a single cell or an ensemble of a few to many cells.

Q24. The process by which unwanted structures within the cell are engulfed and digested within the lysosome is known as:

• A. Endocytosis
• B. Exocytosis
• C. Hydrolysis
• D. Autophagy✓

Explanation: Autophagy is a type of endocytosis that involves the engulfment and digestion of damaged or unnecessary cell parts by the cell itself. This process is essential for maintaining cell health and survival

Q25. The plants having foreign DNA incorporated into their cells are called:

• A. Colonal plants
• B. Transgenic plants✓
• C. Bio tech plants
• D. Tissue cultured plants

Explanation: The term transgenic indicates an organism that contains genetic material from a foreign source. Transgenic plants are plants that have had foreign DNA incorporated into their cells through genetic engineering techniques.

Q26. Pasteurization technique is widely used for preservation of:

• A. Water
• B. Heat
• C. Milk products✓
• D. Vaccines

Explanation: Pasteurization is a technique to remove pathogenic organisms in certain foods and liquids. In water, bacteria is killed through the process of chlorination. Hence, the only remaining viable option is option C : Milk products.

Q27. The production of genetically identical copies of organisms by asexual reproduction is called:

• A. Genetic engineering
• B. Integrated disease management
• C. Hydroponic culture technique
• D. Cloning✓

Explanation: The production of genetically identical copies of organisms by asexual reproduction is called cloning.

Q28. The _ model of plasma membrane suggests that proteins are embedded in lipid bilayer.

• A. Unit membrane
• B. Fluid mosaic✓
• C. Permeable
• D. Ultracentrifuge

Explanation: According to the Fluid Mosaic Model, cell membranes are quasi-fluidic in nature with a viscous lipid bilayer having proteins at places like mosaic both on the outer surface and embedded inside. Singer and Nicolson have described the cell membrane as a 'protein iceberg' in the sea of lipids.

Q29. The function of nucleolus is to make:

• A. rDNA
• B. RNA
• C. Ribosomes✓
• D. Chromosomes

Explanation: The function of the nucleolus is to make ribosomes. The nucleolus is a distinct subcompartment within the cell nucleus, and it plays a vital role in ribosome biogenesis, which is the process of producing ribosomes, the cellular machinery responsible for protein synthesis. The nucleolus is responsible for making ribosomes by transcribing, processing, and assembling the components of ribosomes before exporting them to the cytoplasm, where they perform their crucial role in protein synthesis. Ribosomes are essential cellular structures involved in protein synthesis. They read the genetic information encoded in messenger RNA (mRNA) and use this information to assemble amino acids into polypeptide chains, which eventually fold into functional proteins.

Q30. Lipid metabolism is the function of:

• A. Mitochondria
• B. Sarcoplasmic reticulum
• C. RER
• D. SER✓

Explanation: Fact: Smooth endoplasmic reticulum(SER) is involved in lipid metabolism.

Q31. The enzymes of lysosomes are synthesized on:

• A. RER✓
• B. SER
• C. Chloroplast
• D. Golgi apparatus

Explanation: All enzymes are proteins in nature. Lysosomal enzymes are synthesized on RER then transported with the help of SER towards Golgi complex from where they bud off in the form of primary lysosomes.

Q32. Centrioles are made up of _ microtubules:

• A. 9
• B. 27✓
• C. 3
• D. 12

Explanation: Centrioles are cylindrical structures found in animal cells and are involved in cell division. Each centriole is composed of nine microtubule triplets, arranged in a cylindrical shape. Each triplet consists of three microtubules, resulting in a total of 27 microtubules forming the structure of a centriole.

Q33. Which of the following structures is absent in higher plants and found in animal cells:

• A. Centriole✓
• B. Cytoskeleton
• C. Mitochondria
• D. Cytoplasm

Explanation: Centrioles assist in arranging microtubules to form the spindle fibers during chromosome segregation. In higher plant cells, microtubules can form spindle fibers without the help of centrioles.

Q34. The soluble part of cytoplasm or fluid that remains when all organelles are removed is known as:

• A. Solution
• B. Gelatin material
• C. Cytoskeleton
• D. Cytosol✓

Explanation: Cytosol refers to the soluble, fluid portion of the cytoplasm that remains when all organelles are removed. It contains various molecules, ions, and enzymes necessary for cellular metabolism.

Q35. The outer membrane of the nuclear envelope is at places continuous with the:

• A. Golgi Apparatus
• B. Endoplasmic Reticulum✓
• C. Lysozomes
• D. Peroxisomes

Explanation: The outer nuclear membrane is continuous with the endoplasmic reticulum, so the space between the inner and outer nuclear membranes is directly connected with the lumen of the endoplasmic reticulum.

Q36. Down's syndrome is a result of non-disjunction of_ pair of chromosomes that fails to segregate:

• A. 21st✓
• B. 22nd
• C. 18th
• D. 24th

Explanation: Down's syndrome, also known as trisomy 21, is a result of the non-disjunction of the 21st pair of chromosomes. In individuals with Down's syndrome, there is an extra copy of chromosome 21, leading to characteristic developmental and physical differences.

Q37. _ is most abundant carbohydrate in nature.

• A. Waxes
• B. Glycerol
• C. Starch
• D. Cellulose✓

Explanation: Cellulose, a fibrous carbohydrate found in all plants, is the structural component of plant cell walls. Because the earth is covered with vegetation, cellulose is the most abundant of all carbohydrates, accounting for over 50% of all the carbon found in the vegetable kingdom.

Q38. Which of the following is a keto sugar:

• A. Glyceraldehyde
• B. Dihydroxy-acetone✓
• C. Ribose
• D. Glucose

Explanation: Dihydroxy-acetone is a keto sugar. It is a three-carbon sugar with a ketone functional group.

Q39. Amino acid in which the R-group is hydrogen is:

• A. Glycine✓
• B. Alanine
• C. Leucine
• D. Valine

Explanation: Glycine is the simplest stable amino acid with the molecular formula C2H5NO2.

Q40. Acyl-glycerols like fats and oils are esters formed by condensation reaction between:

• A. Fatty acids and water
• B. Fatty acids and alcohols✓
• C. Fatty acids and glucose
• D. Fatty acids and phosphates

Explanation: Acyl-glycerols, such as fats and oils, are esters formed by a condensation reaction between fatty acids and alcohols. In this reaction, a glycerol molecule reacts with three fatty acid molecules, resulting in the formation of a triglyceride.

Q41. Which of the following is purine:

• A. Guanine✓
• B. Cytosine
• C. Thymine
• D. Uracil

Explanation: Guanine is a purine base. It is one of the four nitrogenous bases found in DNA and RNA.

Q42. If the co-factor is covalently or tightly and permanently bonded to enzyme then it will be called:

• A. Coenzyme
• B. Prosthetic group✓
• C. Activator
• D. Apoenzyme

Explanation: A prosthetic group is a non-protein molecule that is tightly and permanently bound to an enzyme. It is necessary for the enzyme's structure and function.

Q43. Optimum pH value for the working of pancreatic lipase is:

• A. 4.50
• B. 7.60
• C. 2.00
• D. 9.00✓

Explanation: Optimum pH values for the catalytic activity of pepsin, sucrose, catalase and pancreatic lipase are 2.00, 4.50, 7.00 and 9.00, respectively.

Q44. The view that active site of an enzyme is flexible and when a substrate combines with it, cause changes in enzyme structure is known as:

• A. Lock & key model
• B. Induced fit model✓
• C. Sliding filament model
• D. Specificity model

Explanation: According to the lock and key model, the active site of an enzyme is a rigid structure. The sliding filament model explains muscle movement, while the specificity model means that every enzyme reacts with a specific substrate.

Q45. All coenzymes are derived from:

• A. Proteins
• B. Metal ions
• C. Carbohydrates
• D. Vitamins✓

Explanation: Coenzymes are small organic molecules that assist enzymes in catalyzing biochemical reactions. They are often derived from vitamins, which are essential organic compounds that the body requires in small amounts for various metabolic processes.

Q46. Reverse transcription is used to make DNA copies of:

• A. Host RNA
• B. Viral RNA✓
• C. Host DNA
• D. Viral DNA

Explanation: The retroviruses have a special enzyme called reverse transcriptase, which can convert a single-stranded RNA genome into double stranded viral DNA.

Q47. Antibiotics are produced by fungi and certain bacteria of group:

• A. Actinomycetes✓
• B. Oomycetes
• C. Ascomycetes
• D. Basidiomycetes

Explanation: Antibiotics are synthesized and secreted by certain bacteria (actinomycetes) and fungi. (PTB)

Q48. Which of the following bacteria have more lipids in their cell wall?

• A. Gram-positive bacteria have more lipids in their cell wall
• B. Gram-negative bacteria have more lipids in their cell wall✓
• C. Lipids are absent in cell wall of both gram positive and negative bacteria
• D. Both have equal amount of lipids

Explanation: Gram-negative bacteria have a more complex cell wall structure compared to gram-positive bacteria. The outer membrane of gram-negative bacteria contains lipopolysaccharides (LPS), which are lipid-rich molecules. This presence of LPS contributes to a higher lipid content in the cell wall of gram-negative bacteria. In contrast, gram-positive bacteria have a simpler cell wall structure with a thicker layer of peptidoglycan and fewer lipids.

Q49. Fungi which cause thrush in humans:

• A. Sarcomeres
• B. Candidiasis✓
• C. Lovastatin
• D. Aspergillus

Explanation: Excess growth of Candida fungus in the mouth causes a condition known as “Oral thrush” or ”Oral Candidiasis”.

Q50. When beef which is not properly cooked is consumed by humans, they become infected by:

• A. Tapeworm✓
• B. Hookworm
• C. Pinworm
• D. Roundworm

Explanation: Tapeworm infection is caused by eating improperly cooked beef which usually contains the tapeworm "Taenia Saginata."

Q51. Sleeping sickness in humans is caused by:

• A. Trypanosoma✓
• B. Anopheles
• C. Plasmodium
• D. Andes

Explanation: Sleeping sickness, also known as African trypanosomiasis, is caused by various species of Trypanosoma parasites, with Trypanosoma brucei being the primary causative agent. It is transmitted to humans through the bite of infected tse tse flies.

Q52. Schistosoma is a parasite that lives in the _ of the host.

• A. Intestine
• B. Kidney
• C. Liver
• D. Blood✓

Explanation: Schistosoma parasites can penetrate the skin of a person wading through contaminated water. The parasites mature into adult worms within weeks and live in the blood vessels of the body.

Q53. The cavity between body wall and alimentary canal is:

• A. Coelom✓
• B. Mesoderm
• C. Endoderm
• D. Mesoglea

Explanation: Coelom is a cavity between the body wall and alimentary canal which is lined by mesoderm.

Q54. The layer which forms the lining of digestive tract and glands of digestive system is:

• A. Ectoderm
• B. Mesoderm
• C. Endoderm✓
• D. Mesoglea

Explanation: The endoderm is the source of epithelial lining of the digestive tract along with pancreas and gall-bladder.

Q55. Which one of the following vitamins is produced by microflora of large intestine?

• A. Vitamin K✓
• B. Vitamin C
• C. Vitamin A
• D. Vitamin D

Explanation: Vitamin K is majorly synthesized by intestinal microflora. Vitamin K is produced by the microflora (bacteria) present in the large intestine of humans. These bacteria produce various forms of vitamin K, including vitamin K1 (phylloquinone) and vitamin K2 (menaquinone). Vitamin K plays a crucial role in blood clotting and bone metabolism.

Q56. _ is activated to_ by Enterokinase enzyme secreted by the lining of duodenum:

• A. Pepsinogen, Pepsin
• B. Pepsinogen, Trypsin
• C. Trypsinogen, Trypsin✓
• D. Chymotrypsinogen, Chymotrypsin

Explanation: Trypsinogen is activated to trypsin by the enzyme Enterokinase/Enteropeptidase, which is secreted by the lining of the duodenum. Trypsin is an important digestive enzyme involved in the breakdown of proteins in the small intestine. The activation of trypsinogen to trypsin is an essential step in the digestion of dietary proteins.

Q57. Which of the following are absorbed in the large intestine?

• A. Water and Salts✓
• B. Water and Peptones
• C. Salts and glycerol
• D. Amino acids and Sugars

Explanation: The large intestine absorbs water and salts from food waste, turning it into stool.

Q58. Saliva is basically composed of water, mucus, amylase and:

• A. Sodium bicarbonate✓
• B. Sodium chloride
• C. Sodium hydroxide
• D. Hydrocarbons

Explanation: Saliva contains sodium bicarbonate, which helps to maintain the pH balance in the mouth. It acts as a buffering agent, neutralizing the acidity caused by the breakdown of food and preventing damage to the teeth.

Q59. The total inside capacity of lungs is _ for man.

• A. 6.7 litres
• B. 2.5 litres
• C. 7 litres
• D. 5 litres✓

Explanation: In an adult human being when the lungs are fully inflated the total inside capacity of lungs is about 5 litres. (PTB)

Q60. The average life span of red blood cell is about:

• A. 4 months✓
• B. 2 months
• C. 5 months
• D. 1 month

Explanation: The average lifespan of a Red Blood Cell lasts 110-120 days, when they are destroyed by macrophages.

Q61. The lymphatic vessels of the body empty the lymph into blood stream at the:

• A. Abdominal vein
• B. Jugular vein
• C. Sub-clavian vein✓
• D. Bile duct

Explanation: The thoracic duct is the largest lymphatic vessel within the human body. Lymph enters into left subelavain vein through thoracic duct.

Q62. Right atrium is separated from right ventricle by:

• A. Tricuspid Valve✓
• B. Bicuspid valve
• C. Semilunar valve
• D. Septum

Explanation: The valve lying between the right atrium and the right ventricle is known as the tricuspid valve due to it having three flaps.

Q63. Sites of filtration in nephron are:

• A. Glomerulus and Bowman's Capsule✓
• B. Proximal and distal end
• C. Ascending and descending arm
• D. Loop of henle

Explanation: The Glomerulus and Bowman’s capsule are sited of filtration in the nephron while ascending/descending loop of Henle carries out reabsorption of water and salts.

Q64. Antidiuretic hormone increases the reabsorption of:

• A. Amino acids
• B. Salt
• C. Ammonia
• D. Water✓

Explanation: Antidiuretic hormone is a hormone produced by the hypothalamus and released by the pituitary gland, which regulates the reabsorption of water.

Q65. Active uptake of_ in the ascending limb or thick loop of Henle is promoted by the action of aldosterone:

• A. K+
• B. Cl-
• C. Ca++
• D. Na+✓

Explanation: The active uptake of sodium (Na+) in the ascending limb or thick loop of Henle is promoted by the action of aldosterone. Aldosterone is a hormone produced by the adrenal glands that acts on the distal tubules and collecting ducts of the nephron to enhance sodium reabsorption. By increasing sodium reabsorption, aldosterone helps regulate sodium and water balance in the body and plays a role in blood pressure regulation.

Q66. The process through which the body maintains the internal environment from the fluctuations of external environment is called as:

• A. Behavior of organisms
• B. Adaptation
• C. Thermoregulation
• D. Homeostasis✓

Explanation: Homeostasis refers to the process by which the body maintains a stable internal environment despite fluctuations in the external environment. It involves various physiological mechanisms that regulate factors such as temperature, pH, blood glucose levels, and more, ensuring optimal conditions for cells and tissues to function properly.

Q67. Active pumping out of Na+ occurs at which part of nephron:

• A. Proximal tubule✓
• B. Descending loop of Henle
• C. Ascending loop of Henle
• D. Collecting ducts

Explanation: Primary site of reabsorption of sodium ions in the nephron is the ascending loop of Henle. The ascending loop of Henle is responsible for the active reabsorption of sodium and other solutes. Sodium is actively pumped out of the tubule cells into the interstitial fluid, creating a concentration gradient that allows for the reabsorption of other solutes in the distal parts of the nephron.

Q68. The structures which respond when they are stimulated by impulse coming through motor neuron are:

• A. Receptors
• B. Responders
• C. Transducers
• D. Effectors✓

Explanation: Motor neurons carry impulses from the central nervous system to effector organs such as muscles or glands.

Q69. Thalamus and cerebrum are the part of:

• A. Fore brain✓
• B. Mid brain
• C. Hind brain
• D. Spinal cord

Explanation: The forebrain is the largest region of the brain, containing the entire cerebrum and thalamus, along with other nested structures.

Q70. There is also EVIDENCE that high levels of _ may contribute to the onset of Alzheimer's disease.

• A. Mg
• B. Mo
• C. Al✓
• D. Ca

Explanation: There is some evidence suggesting that high levels of aluminum (Al) may contribute to the onset of Alzheimer's disease. The factors such as genetic predisposition, age, and lifestyle factors are also believed to play significant roles in the development of Alzheimer's disease.

Q71. L-dopa or Levodopa is used to get some relief from?

• A. Epilepsy
• B. Alzheimer’s disease
• C. Parkinson's disease✓
• D. Dementia

Explanation: L-dopa or Levodopa is primarily used in the treatment of parkinson's disease. It is a precursor to dopamine and helps replenish dopamine levels in the brain, providing relief from motor symptoms such as tremors, stiffness, and bradykinesia.

Q72. Spermatogonia differentiate directly into

• A. Primary spermatocytes✓
• B. Secondary spermatocytes
• C. Spermatozoa
• D. Spermatids

Explanation: Spermatogonia differentiate into spermatocytes, which then undergo meiosis to later form mature sperm cells.

Q73. Treponema pallidum causes

• A. AIDS
• B. Genital herpes
• C. Syphilis✓
• D. Gonorrhea

Explanation: Treponema pallidum is the bacterium responsible for causing syphilis, a sexually transmitted infection.

Q74. What is the location of interstitial cells in testes?

• A. Inside the seminiferous tubules
• B. Between the seminiferous tubules✓
• C. Among the germinal epithelial cells
• D. Around the testes

Explanation: The interstitial cells, also known as Leydig cells, are located in the connective tissue spaces between the seminiferous tubules in the testes. These cells produce and secrete testosterone, which is an important male sex hormone involved in the development and maintenance of male reproductive tissues and secondary sexual characteristics. The seminiferous tubules, on the other hand, are the site of sperm production within the testes.

Q75. A type of cells in human testes which produce testosterone are called

• A. Germ cells
• B. Sertoli cells
• C. Interstitial cells✓
• D. Spermatocytes

Explanation: Interstitial cells, also known as Leydig cells, are located in the connective tissue spaces between the seminiferous tubules in the testes. They are responsible for the production and secretion of testosterone, which is an essential male sex hormone.

Q76. The hormone produced from corpus luteum is:

• A. Prolactin
• B. FSH
• C. Progesterone✓
• D. LH

Explanation: The corpus luteum is a temporary endocrine structure that forms in the ovary after ovulation. Its main function is to produce progesterone, which is crucial for the maintenance of the uterine lining (endometrium) during the second half of the menstrual cycle and early pregnancy. So C is the correct option.

Q77. The length of myofibril from one Z-band to the next is described as:

• A. Sarcolemma
• B. Sarcoplasm
• C. Sarcomere✓
• D. Muscle fibre

Explanation: The region lying between two Z-bands is called a Sarcomere. Sarcomeres are the functional units of muscle contraction and are composed of actin and myosin filaments.

Q78. The Ca++ ions released during a muscle fiber contraction attach with:

• A. Myosin
• B. Actin
• C. Troponin✓
• D. Tropomyosin

Explanation: Ca2+ ions attach to troponin during muscle fiber contraction. Troponin is a regulatory protein complex found on the actin filaments in muscle fibers. When Ca2+ ions bind to troponin, it induces a conformational change that moves tropomyosin away from the binding sites on actin, allowing myosin to bind and initiate muscle contraction.

Q79. The joint that allows the movement in several directions is called:

• A. Hinge joint
• B. Ball and Socket joint✓
• C. Cartiligious joint
• D. Fibrous joint

Explanation: Ball and socket joint allows movement in all directions as it enables movement around an indefinite number of axes.

Q80. Where can we find H zone in the figure of fine structure of skeletal muscle's myofibril?

• A. In the mid of A band✓
• B. In I band
• C. Besides the Z line
• D. Along the I band

Explanation: The H zone appears as a lighter band bisecting the A-band at the center of a sarcomere.

Q81. First vertebra of cervical region of vertebral column is known as:

• A. Atlas✓
• B. Sacral
• C. Thoracic
• D. Axis

Explanation: The first vertebra of the cervical region is known as the atlas. It supports the skull and allows for nodding movements of the head.

Q82. Chemically, insulin and glucagon are:

• A. Carbohydrates
• B. Proteins✓
• C. Lipids
• D. Nucleic Acids

Explanation: Insulin and glucagon are both peptide (protein) hormones secreted by the beta and alpha cells of pancreas respectively.

Q83. Hormones secreted by anterior pituitary and which controls the secretion of hormones of other endocrine glands are known as:

• A. Release factor
• B. Inhibitor
• C. Accelerator
• D. Tropic or trophic hormones✓

Explanation: Hormones secreted by the anterior pituitary that control the secretion of hormones from other endocrine glands are known as tropic or trophic hormones. These hormones include thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle-timulating hormone (FSH), and leutinizing hormone (LH). They stimulate the target glands to produce and release their own hormones, thereby controlling their activity and function.

Q84. Alpha cells of Islets of Langerhans secrete hormone called:

• A. Glucocorticoid
• B. Insulin
• C. Glucagon✓
• D. Aldosterone

Explanation: Glucagon is a peptide hormone secreted by Alpha cell of Islets of Langerhans in the pancreas. Glucagon is involved in raising blood sugar levels by promoting the breakdown of glycogen stored in the liver, which releases glucose into the bloodstream.

Q85. Which of the following is the function of glucagon hormone?

• A. Glycogen to Glucose✓
• B. Glucose to Glycogen
• C. Glucose to Lipids
• D. Glucose to Proteins

Explanation: Glucagon is a hormone released by the pancreas, which help maintain blood sugar levels. It does this by converting glycogen into glucose, thus increasing blood sugar.

Q86. In passive immunity which of the following components are injected into body?

• A. Antigens
• B. Immunogens
• C. Serum
• D. Immunoglobulins✓
• E. C and d

Explanation: Immunoglobulins, also known as antibodies, are injected for passive immunity. They are specific proteins produced by the immune system in response to the presence of antigens. They provide temporary protection against infectious diseases and are commonly used for the treatment of certain conditions where immediate immunity is required, such as in cases of exposure to certain viruses or toxins.

Q87. Which part of the antibody recognizes the antigen during immune response?

• A. Heavy part
• B. Variable part✓
• C. Light part
• D. Constant part

Explanation: The variable regions of an antibody are responsible for antigen recognition and binding. Antibodies are the soluble proteins produced in response to an antigen by the B-cells. They are Y-shaped molecules consisting of four polypeptide chains: two identical heavy chains and two identical light chains. The two ends or tips of the Y-shaped molecule of an antibody are the variable regions, which are the parts of the antibody that combines with the antigen. The variable regions of a particular antibody can only join with a particular antigen.

Q88. Two identical light chains and two identical heavy chains in antibody molecule are linked by:

• A. Disulphide bridges✓
• B. Peptide bond
• C. Glycerol bond
• D. Ionic bond

Explanation: Disulphide bonds can be used to hold different sub-units of protein complexes together, as is found in antibodies between the light chains and between the heavy chains.

Q89. Antibodies are produced against invading cells by:

• A. Lymphocytes✓
• B. Basophils
• C. Phagocytes
• D. Neutrophills

Explanation: Antibodies are primarily produced by lymphocytes, specifically B-cells, in response to invading cells or antigens.

Q90. In the structural diagram of an antibody molecule which portion is occupied by variable chains?

• A. Lower region
• B. Upper region✓
• C. Middle region
• D. In between chains

Explanation: The variable chains of an antibody molecule, both the variable heavy chain and the variable light chains, occupy the upper region of the structural diagram. The region is also known as the antigen-binding region. It is responsible for the specificity of the antibody and its ability to bind to different antigens. The lower region of the antibody, known as the constant region, does not contain the variable chains.

Q91. Every molecule of NADH, fed into ETC produces:

• A. 2 ATP
• B. 3 ATP✓
• C. 4 ATP
• D. 6 ATP

Explanation: Every molecule of NADH (nicotinamide adenine dinucleotide) that enters the Electron Transport Chain (ETC) during cellular respiration produces approximately 3 molecules of ATP. This occurs through a process known as oxidative phosphorylation. The high-energy electrons carried by NADH are transferred along the electron transport chain, consisting of a series of protein complexes in the inner mitochondrial membrane. As electrons move through this chain, protons (H+) are pumped across the membrane, creating a proton gradient. This proton gradient is then used by the enzyme ATP synthase to generate ATP from adenosine diphosphate (ADP) and inorganic phosphate (Pi). The exact number of ATP molecules generated per NADH can vary slightly, but, on average, it is considered to be around 3 molecules of ATP. The process is more complex for FADH2 (another electron carrier), which typically yields about 2 molecules of ATP. These ATP molecules contribute to the overall energy production in cellular respiration.

Q92. Final acceptor of electrons in respiratory chain is:

• A. Cytochrome A
• B. Oxygen✓
• C. Cytochrome a3
• D. Cytochrome C

Explanation: The final acceptor of electrons in the respiratory chain is oxygen (O2). During oxidative phosphorylation, which is the last stage of cellular respiration, electrons are transferred through a series of protein complexes in the inner mitochondrial membrane (or the plasma membrane in prokaryotes). This process is part of the electron transport chain.

Q93. The end product of anaerobic respiration in humans and other mammals is:

• A. Pyruvic acid
• B. Ethanol
• C. Lactic acid✓
• D. Glucose

Explanation: The end product of anaerobic respiration in humans and other mammals is lactic acid. In the absence of sufficient oxygen, cells resort to anaerobic respiration to generate energy. Anaerobic respiration involves the incomplete breakdown of glucose and results in the production of lactic acid as a byproduct. The specific process is known as lactic acid fermentation. During this process, pyruvate, which is an intermediate product of glycolysis, is converted into lactic acid. This reaction helps to regenerate NAD+ from NADH, allowing glycolysis to continue in the absence of oxygen.

Q94. A biochemical process which occurs within a cell to breakdown complex compounds to produce energy is called:

• A. Respiration✓
• B. Photosynthesis
• C. Oxidation Reduction
• D. Photophosphorylation

Explanation: The biochemical process that occurs within a cell to break down complex compounds to produce energy is called cellular respiration. Cellular respiration is a set of metabolic reactions that take place in cells to extract energy from organic molecules, such as glucose. The energy released during cellular respiration is used to produce adenosine triphosphate (ATP), which serves as the primary energy currency for cellular activities.

Q95. Which part of chlorophyll molecule absorbs light?

• A. Phytol
• B. Porphyrin ring✓
• C. Pyrrole
• D. Thylakoid membrane

Explanation: The part of the chlorophyll molecule that absorbs light is the porphyrin ring, which is a complex cyclic structure containing a centrally coordinated magnesium ion (Mg2+). The porphyrin ring is responsible for the pigment's ability to absorb light energy during the process of photosynthesis. The porphyrin ring consists of alternating single and double bonds, creating a conjugated system. This conjugated system allows chlorophyll to absorb light in the visible spectrum.The absorption of light by chlorophyll is most efficient in the blue and red regions of the electromagnetic spectrum.

Q96. The DNA molecule formed from messenger-RNA by reverse transcriptase is called?

• A. Complementary DNA✓
• B. Recombinant DNA
• C. Chimeric DNA
• D. Plasmid DNA

Explanation: The DNA molecule formed from messenger-RNA (mRNA) by reverse transcriptase is called complementary DNA (cDNA). Reverse transcriptase enzyme synthesizes cDNA using mRNA as a template.

Q97. The agent which separates the two strands of DNA in PCR is?

• A. DNA ligase
• B. Primer
• C. Heat✓
• D. Helicase

Explanation: In PCR (polymerase chain reaction), the two strands of DNA are separated by raising the temperature. The process of heating the DNA to separate the strands is called denaturation. It allows the DNA to become single-stranded and available for further steps in PCR.

Q98. Cystic fibrosis patients lack a gene that codes for trans-membrane carriers of?

• A. Na+ ions
• B. Cl- ions✓
• C. Ca++ ions
• D. K+ ions

Explanation: Cystic fibrosis is a genetic disorder caused by a mutation in the cystic fibrosis trans-membrane conductance regulator (CFTR) gene. This gene codes for a protein involved in the transport of chloride ions (Cl-) across cell membranes. In individuals with cystic fibrosis, the CFTR protein is either absent or dysfunctional, leading to impaired chloride ion transport. The imbalance of chloride ions affects the movement of water in and out of cells, particularly in the respiratory and digestive systems. This results in the production of thick, sticky mucus that clogs the airways and obstructs the pancreas, leading to various symptoms and complications associated with cystic fibrosis

Q99. The phage commonly used as a vector in genetic engineering is?

• A. Lambda phage✓
• B. Gamma phage
• C. T2 phage
• D. T4 phage

Explanation: Modified Lambda phages are used as a vector to introduce foreign DNA into a cell due to their efficiency at packaging and injecting DNA into the cell.

Q100. Restriction endonucleases are naturally occurring enzymes of:

• A. Viruses
• B. Bacteria✓
• C. Fungi
• D. Plants

Explanation: Restriction endonucleases cleave into fragments near or at recognition sites. They are found in bacteria as a defence mechanism against viruses.

Q101. In an ecosystem mycorrhizae are an example of:

• A. Predation
• B. Symbiosis
• C. Mutualism✓
• D. Parasitism

Explanation: Mycorrhizae are a symbiotic association between fungi and plant roots where the plant roots provide the fungus with favourable conditions for growth and nutrients, while the fungus increases the plants water and nutrient absorption capabilities.

Q102. As a result of destruction of ozone layer there is significant increase in:

• A. Ultra-violet radiations✓
• B. Greenhouse gases
• C. Nitrogen oxide
• D. Sulphur oxide

Explanation: The ozone layer absorbs Ultra-violet radiation. Depletion of ozone layer results in increased amount of Ultra-violet radiation reaching the Earth’s surface.

Q103. Higher rate of a biological activity in a nutrient rich pond water is called:

• A. Water pollution
• B. Air pollution
• C. Eutrophication✓
• D. Industrial effects

Explanation: Eutrophication is characterized as the excess growth of algae or aquatic plants due to an increase in one or more growth limiting factors such as nutrients, sunlight, and carbon dioxide.

Q104. Living part of ecosystem is:

• A. Lithosphere
• B. Hydrosphere
• C. Community
• D. Biosphere✓

Explanation: The biosphere is the part of an ecosystem which integrates all living organisms and their relationship with one another.

Q105. A living association between two living organisms of different species which is beneficial to both the partners is called:

• A. Commensalism
• B. Parasitism
• C. Mutualism✓
• D. Predation

Explanation: Mutualism is a form of a symbiotic relationship where all involved species benefit from their interactions with one another.

Q106. The structures which are reduced during the course of evolution and have no apparent function are called:

• A. Regenerated organs
• B. Vestigial organs✓
• C. Saltatory organs
• D. Useless organs

Explanation: Vestigial organs are organs which are thought to be remnants of organs that once served some purpose but are now no longer functional or are of altered/reduced function. Examples of vestigial organs in humans include the appendix, tailbone (coccyx), and wisdom teeth.

Q107. When a gene suppresses the effect of another gene at another locus the phenomenon is termed as:

• A. Over dominance
• B. Pleiotropy
• C. Epistasis✓
• D. Codominance

Explanation: Epistasis is the phenomenon when one gene locus modifies or influences a phenotype of another gene locus.

Q108. Phenylketonuria is an example of:

• A. Polyploidy
• B. Transmutation
• C. Inversion
• D. Point mutation✓

Explanation: Phenylketonuria is characterized by a mutation causing the loss of function of the hepatic enzyme phenylalanine hydroxylase through a mutation in the genome. Point mutation occurs when one base pair has been altered, added, or deleted from DNA or RNA. Hence, Phenylketonuria is an example of point mutation.

Q109. A situation in which one gene affects two or more unrelated characters is called:

• A. Epistasis
• B. Pleiotropy✓
• C. Dominance relation
• D. Polygenes

Explanation: Pleiotropy occurs when one gene influences two or more seemingly unrelated phenotypic traits. Such a gene that exhibits multiple phenotypic expression is called a pleiotropic gene.

Q110. The mutation which causes change in the sequence of DNA at a given position is called:

• A. Point mutation✓
• B. Chromosomal mutation
• C. Translocation
• D. Inversion

Explanation: Point mutation is the phenomenon that occurs when a single nucleotide is added, altered, or deleted from an organisms genome. It alters the sequence of DNA.

Q111. Hydrogen burns in chlorine to produce hydrogen chloride. The ratio of masses of reactants in the chemical reaction is:H2 + Cl2 → 2HCl

• A. 1:35.5✓
• B. 2:35.5
• C. 1:71
• D. 2:70

Explanation: Mass of 1 mole of H2 = 2x1= 2g Mass of 1 mole of Cl2 = 2x35.5 = 71g 2 : 71 1 : 35.5

Q112. A sample of Neon is found to exist as 20Ne, 21Ne, 22Ne. Mass spectrum of ‘Ne’ is as follows: What is the relative atomic mass (Ar value) of Neon?

• A. 20.18✓
• B. 20.28
• C. 20.10
• D. 20.22

Explanation: Relative atomic mass = Sum of product of isotopic masses and relative abundances/100 Relative atomic mass = [(20 × 90.92) + (21 × 0.26) + (22 × 8.82)] / 100 Relative atomic mass = 20.179 ≈ 20.18

Q113. The coordination number of Na+ in NaCl crystal is:

• A. 6✓
• B. 2
• C. 4
• D. 8

Explanation: The coordination number is the number of ions that immediately surround an ion of the opposite charge within a crystal lattice. If you examine the figure below, you will see that there are six chloride ions immediately surrounding a single sodium ion. The coordination number of sodium is 6.

Q114. There are four gases H2, He, N2 and CO2 at 0 °C. Which gas shows greater non-ideal behavior?

• A. He
• B. CO2✓
• C. H2
• D. N2

Explanation: Carbon dioxide is a linear molecule consisting of one carbon atom bonded to two oxygen atoms. CO2 exhibits greater non-ideal behavior compared to helium due to the presence of strong intermolecular forces such as dipole-dipole interactions.

Q115. Correct order of energy in the given subshells is:

• A. 5s > 3d > 3p > 4s
• B. 5s > 3d > 4s > 3p✓
• C. 3p > 3d > 5s > 4s
• D. 3p > 3d > 4s > 5s

Explanation: The order of energy in subshells is based on the principal quantum number (n) and the angular momentum quantum number (l). The principal quantum number determines the size of the orbital, while the angular momentum quantum number determines the shape of the orbital. The order of energy in subshells is as follows: s subshell (l = 0) p subshell (l = 1) d subshell (l = 2) f subshell (l = 3) The orbitals are organized in such a way that the lower principal quantum numbers (n) have lower energy, and within a given n, the subshells follow the order s < p < d < f. The s subshell has the lowest energy, followed by the p subshell, the d subshell, and so on. This is because the s subshell has the lowest angular momentum, and the angular momentum determines the energy of the orbital. The correct order is: 1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p < 5s < 4d < 5p < 6s...

Q116. Number of electrons in the outermost shell of chloride ion (Cl-) is:

• A. 17
• B. 3
• C. 1
• D. 8✓

Explanation: Chlorine atom has 7 electrons in it's valence shell, however the question is asking about chloride ion which has 1 extra electron. So the correct answer would be 8.

Q117. According to valence shell electron pair repulsion theory, the repulsive forces between the electron pair of central atom of molecule are in the order:

• A. Lone Pair - Lone Pair > Lone Pair - Bond Pair > Bond Pair - Bond Pair✓
• B. Lone Pair - Bond Pair > Lone Pair - Lone Pair > Bond Pair - Bond Pair
• C. Bond Pair - Bond Pair > Lone Pair - Lone Pair > Lone Pair - Bond Pair
• D. Lone Pair - Bond Pair > Bond Pair - Bond Pair > Lone Pair - Lone Pair

Explanation: According to the VSEPR theory, lone pairs of electrons occupy more space than bonding pairs. As a consequence, this is an order of the magnitude of repulsion. Lone Pair - Lone Pair > Lone Pair - Bond Pair > Bond Pair - Bond Pair The greatest repulsion is between 2 lone pairs. Followed by repulsion between one lone pair and one bonding pair. The weakest repulsion is between 2 bonding pairs, the magnitude of repulsion between bonding pairs of electrons depends on the electronegativity difference between a central atom and the other atoms.

Q118. In crystal lattice of ice, each O-atom of water molecule is attached to

• A. Four H-atoms✓
• B. Three H-atoms
• C. One H-atom
• D. Two H-atoms

Explanation: In the solid state (ice), intermolecular interactions lead to a highly ordered but loose structure in which each oxygen atom is surrounded by four hydrogen atoms; two of these hydrogen atoms are covalently bonded to the oxygen atom, and the two others (at longer distances) are hydrogen bonded to the oxygen atom’s unshared electron pairs.

Q119. Heat of formation (∆Hf°) for CO2 is:

• A. -394 kJ/mole✓
• B. +394 kJ/mole
• C. -294 kJ/mole
• D. -390 kJ/mole

Explanation: The heat of formation (∆Hf°) for carbon dioxide (CO2) is: ∆Hf° = -394 kj/mol The negative sign indicates that the formation of one moleucle of CO2 from its constituent elements (carbon and oxygen) releases 394 kj of energy. In other words, it is an exothermic process, where energy is released during the formation of CO2 .

Q120. Reactants have high energy than products in:

• A. Exothermic reactions✓
• B. Endothermic reactions
• C. Photochemical reactions
• D. Non-spontaneous reactions

Explanation: As shown in the energy graph, in an exothermic reaction, reactants have more energy than products. Products are more stable than the reactants.

Q121. If 18.0 g of glucose is dissolved in 1 kg of water, boiling point of this solution should be:

• A. 100.52 °C
• B. 100.00 °C
• C. 100.052 °C✓
• D. Less than 100 °C

Explanation: Mass of glucose = 18 g Mass of solvent = 1 kg Boiling point of pure water = 100°C n (glucose) = 18 / [6(12) + 12(1) + 6(18)] = 18 /180 = 0.1 moles Molality (glucose) = n / mass of solvent = 0.1 / 1 = 0.1 molal ∆Tb = kb × molality = 0.52 × 0.1 = 0.052 Kelvin New boiling point = Boiling point of pure water + ∆Tb New boiling point = 100 + 0.052 = 100.052°C

Q122. Molal freezing point constant of water is:

• A. 1.86✓
• B. 2.86
• C. 11.86
• D. 0.52

Explanation: The molal freezing point depression constant for H2O, Kf , is given as 1.86 °C kg/mole. Thus a 1.00 m aqueous solution freezes at -1.86 °C instead of 0.00 °C which is the normal freezing point for water.

Q123. In the figure given below, the electron flow in external circuit is from:

• A. Copper to zinc electrode
• B. Right to left
• C. Porous partition to zinc electrode
• D. Zinc to copper electrode✓

Explanation: The electrons flow from the oxidation reaction (Zn (s) --> Zn2+ (aq) + 2 e-) to the reduction half-cell (Cu2+ (aq) + 2 e- --> Cu (s)). So the electrons flow from the left to the right (zinc to copper electrode).

Q124. By considering Arrhenius equation, the graph between ‘1/T’ and ‘log K’, which of the following graph represents the relationship between log K and 1/T?

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

Explanation: The original Arrhenius equation is: k = Ae(-Ea/RT) Which can be rewritten as: log k = -Ea/RT log Ae, where Ea log Ae/R is a constant and T is a variable. The slope of the Arrhenius equation is used to calculate activation energy. Arrhenius equation is rearranged it is a linear equation with the form y = mx + b y is log(k), x is 1/T, and m is -Ea/R .

Q125. Which one of the following is a redox reaction?

• A. NaCl + AgNO3 → NaNO3 + AgCl2
• B. 2Cl- → Cl2 + 2e-
• C. 2Na + Cl2 → 2NaCl✓
• D. Na + 1e- → Na

Explanation: The oxidation number of sodium increases from 0 (on the reactants side) to +1 (on the products side), hence sodium is being oxidised. The oxidation number of chlorine decreases from 0 (on the reactants side) to -1 (on the products side), hence chlorine is being reduced. Therefore, we can say that 2Na + Cl2 → 2NaCl is a redox reaction .

Q126. The chemical substance, when dissolved in water, gives “H+” is called:

• A. Acid✓
• B. Base
• C. Amphoteric
• D. Neutral

Explanation: Acids are substances that release hydrogen ions (H+) when dissolved in water. They have a pH value less than 7 and can react with bases to form salts.

Q127. The 'pH' of human blood is:

• A. 6.7 – 8
• B. 7.9
• C. 7.5
• D. 7.35 – 7.4✓

Explanation: The pH of human blood is typically around 7.35 to 7.45, which is slightly alkaline or basic. It is important for the pH of blood to remain within this narrow range as deviations can have adverse effects on bodily functions.

Q128. In zero order reactions, the rate is independent of:

• A. Concentration of the product
• B. Concentration of the reactant✓
• C. Temperature of the reaction
• D. Surface area of the product

Explanation: In zero-order reactions, the rate is independent of the concentration of the reactants. This means that changing the concentration of the reactant does not affect the reaction rate. The rate of reaction is determined by other factors such as the temperature, presence of catalysts, or the surface area of the reactant.

Q129. What is the trend of melting and boiling point of the elements of short periods as we move from left to right in a periodic table?

• A. Melting and boiling points first decrease then increase
• B. Melting and boiling points increase gradually
• C. Melting and boiling points first increase then decrease✓
• D. Melting and boiling points decrease gradually

Explanation: In general, the melting point increases across a period up to group 14 and then decreases from group 14 to group 18. From sodium to aluminum there is metallic bonding, the strength of metallic bonding increases across the period due to an increase in ionic charge (so greater electrostatic attraction) and larger nuclear charge (positively charged nucleus is closer to delocalized electrons so less shielding). Hence, melting/boiling points generally increase. From phosphorus to argon the atoms form simple covalent structures in which the strength of intermolecular forces determines the melting/boiling points. Vanderwaal's forces increase with more electrons and larger molecules. (Silicon however has a giant covalent structure, much stronger bonds, and therefore a high melting/boiling point).

Q130. Along a period, atomic radius decreases. This gradual decrease in radius is due to:

• A. Increase in number of electrons in valence shells
• B. Increase in number of protons in the nucleus✓
• C. Decrease in number of shells
• D. Increase in number of shells

Explanation: Along a period, the number of shells increases (electrons are added to the same principal energy level), and the atomic number increases. More protons attract the valence electrons. Electrons are gradually pulled closer to the nucleus because of the increased positive charge.

Q131. Alkaline earth metal oxides react with water to give hydroxides. The solubility of alkaline earth metal oxides in water increases as we move from top to bottom in a group. Which of the following alkaline earth metal oxides is least soluble in water?

• A. MgO✓
• B. CaO
• C. BaO
• D. SrO

Explanation: Solubility of alkaline earth metal oxides in water increases as we move from top to bottom because lattice energy decreases faster than hydration energy. For the compound to be soluble, its hydration energy must be greater than its lattice energy. Mg is at the top of the group (followed by Ca, Sr, and then Ba), Magnesium oxide (MgO) has low solubility in water. It reacts with water to form magnesium hydroxide Mg(OH)2, but the solubility is relatively limited.

Q132. The electronic structure of carbon monoxide is represented as:

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

Explanation: CO forms a coordinate bond. Carbon has 4 valence electrons and oxygen has 6. Carbon and oxygen form a double bond by sharing two bond pairs, in which both contribute to 2 electrons to form a double bond. Now, oxygen's octet is complete but carbon is still left with 2 valence electrons and has a total of 6. So to attain stability oxygen contributes one of its lone pair of electrons to the carbon atom in the formation of a coordinate bond.

Q133. Which one pair has the same oxidation state of ‘Fe’?

• A. FeSO4 and FeCl3
• B. FeCl2 and FeCl3
• C. FeSO4 and FeCl2✓
• D. Fe2(SO4)3 and FeSO4

Explanation: In both FeSO4 and FeCl2, the oxidation state of Fe is +2.

Q134. Oxidation state of ‘Fe’ in K3[Fe(CN)6] is:

• A. +2
• B. +3✓
• C. -6
• D. -3

Explanation: K has a +1 charge, so K3 is +3. CN has a -1 charge, so (CN)6 is -6. So, +3 + -6 + x = 0 -3 + x = 0 x = +3 So, the oxidation state of 'Fe' in K3[Fe(CN)6] is +3.

Q135. The nature of an aqueous solution of ammonia (NH3) is:

• A. Amphoteric
• B. Neutral
• C. Acidic
• D. Basic✓

Q136. Unpolluted rain water has a pH of:

• A. 4.9
• B. 5.6✓
• C. 5.3
• D. 7.0

Explanation: Unpolluted rain water tends to be slightly acidic due to the presence of carbonic acid formed from the reaction of carbon dioxide (CO2) in the atmosphere with water. The pH of unpolluted rain water is generally around 5.6, although variations may occur depending on local atmospheric conditions.

Q137. In comparison with oxygen gas, a strong triple bond is present between two nitrogen atoms in a molecule and therefore nitrogen gas is:

• A. Highly reactive gas
• B. Completely inert like noble gases✓
• C. Very less reactive gas
• D. Moderately reactive gas

Explanation: The strong triple bond in nitrogen molecule makes it extremely difficult to break hence it is inert.

Q138. The catalyst used in the Haber’s process is:

• A. Magnesium oxide
• B. Aluminium oxide
• C. Silicon oxide
• D. Iron crystals with metal oxide promoters✓

Explanation: Iron crystals with metal oxide promoters are used in the Haber process. Magnesium oxide is used in the dehydrohalogenation of halogenated hydrocarbons and alcohols. Aluminum oxide is used in the dehydration of alcohols to an alkene. Silicon oxide is used in the oxidation of benzene.

Q139. The cis-isomerism is shown by:

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

Explanation: Same functional groups are on the same side (H on one side and CH3 on the other), hence showing cis-isomerism.

Q140. Select the nucleophile from the following examples:

• A. NO2
• B. NH3✓
• C. NO2+
• D. NH4+

Explanation: A nucleophile is electron-rich species and donates electron pairs to electron-deficient species. Therefore, ammonia (NH3) is a nucleophile.

Q141. The introduction of an alkyl group in benzene takes place in the presence of AlCl3 and:

• A. A
• B. B✓
• C. C
• D. D

Explanation: Alkylation of benzene, involves reacting benzene ring with an alkyl halide in the presence of AlCl3 .

Q142. What is the product formed when propene reacts with HBr?

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

Explanation: When propene (CH3-CH=CH2) reacts with hydrogen bromide (HBr), it undergoes an addition reaction to form 2-bromopropane. The hydrogen bromide (HBr) adds to the double bond of propene, resulting in the addition of a bromine atom to one of the carbon atoms and a hydrogen atom to the other carbon atom. The reaction can be represented as follows:CH3​−CH=CH2​+HBr→CH3​−CH(Br)−CH3​Hence, option D is correct.

Q143. The order of reactivity of alkyl halides towards nucleophile is:

• A. RI > RBr > RF > RCl
• B. RI > RBr > RCl > RF✓
• C. RF > RCl > RBr > RI
• D. RF > RBr > RCl > RI

Explanation: The alkyl halides are very reactive due to the highly polarised C - X bond with a large difference in electronegativities of carbon and halogen atoms. The order of reactivity is: iodides > bromides > chlorides > fluorides

Q144. Consider the reaction given below: Which statement is true?

• A. Reagent for I is KOH in alcohol
• B. Reagent for II is KOH in aqueous medium
• C. Reaction I is Debromination
• D. Reaction II is elimination✓

Explanation: Elimination of primary alkyl halides gives alkenes, reaction II is KOH in alcohol and reaction I is KOH in aqueous medium.

Q145. In the following reaction, what product(s) may be formed?C2H5OH + PCl5 → ?

• A. C2H5Cl only
• B. C2H5Cl and HCl
• C. C2H5Cl, POCl3 and HCl✓
• D. C2H5Cl and POCl3

Explanation: The following reaction occurs.

Q146. The name of the following compound is:

• A. Picric acid✓
• B. Nitro phenol
• C. Benzoic acid
• D. Malonic acid

Explanation: Picric acid is 2,4,6-trinitrophenol. Picric acid has a structure consisting of a phenolic ring with three nitro groups (-NO2) attached, making it a yellow crystalline solid with explosive properties.

Q147. Which group gives a yellow precipitate of triiodomethane when warmed with alkaline aqueous iodine?

• A. An amide group, CH3CONH2
• B. Ethyl ketone group, C2H5COR
• C. A primary alcohol group as in propanol, CH3CH2CH2OH
• D. Methyl ketone group, CH3COR✓

Explanation: In the case of ethanal, methyl ketone or a secondary alcohol with a methyl group in the alpha position, a pale yellow precipitate of iodoform or triiodomethane is formed.

Q148. Aqueous phenol decolorizes bromine water to form a white precipitate. What is the structure of the white precipitate formed?

• A. A✓
• B. B
• C. C
• D. D

Explanation: Since the OH group has an electron donating effect, it is an ortho-para director. The following reaction occurs:

Q149. The relative strength of carboxylic acid, water, ethanol, and phenol has the following order of increasing acid strength:

• A. Carboxylic Acid > Phenol > Ethanol > Water
• B. Carboxylic Acid > Phenol > Water > Ethanol✓
• C. Phenol > Carboxylic Acid > Ethanol > Water
• D. Water > Ethanol > Phenol > Carboxylic Acid

Explanation: The phenoxide ion obtained after the removal of a proton is stabilized by resonance whereas the ethoxide loan obtained after the removal of a proton is destabilized by the effect of the -C2H5 group. Therefore, phenol is a stronger acid than ethanol. Ethanol is a weaker acid than water because the electron releasing -C2H5 group in ethanol increases the electron density on oxygen hence the polarity of the O-H bond in ethanol decreases which results in decreasing acidic strength. Hence, the order of increasing acid strength is:Carboxylic acid > Phenol > Water > Ethanol

Q150. What is the structure of alcohol which on oxidation with acidified Na2Cr2O7 gives:

• A. A✓
• B. B
• C. C
• D. D

Explanation: Oxidation of phenyl ethanol gives acetophenone. Please note that the oxidation of primary alcohols gives aldehydes, while the oxidation of secondary alcohols gives ketones. Tertiary alcohols cannot be oxidised at all.

Q151. Which of the following is the structure of ketone?

• A. A
• B. B✓
• C. C
• D. D

Explanation: Ketone is a functional group with the structure R2C=O, where R can be a variety of carbon-containing substituent

Q152. The formation of ester from acetic acid in presence of acid and ethanol is a:

• A. Nucleophilic substitution reaction✓
• B. Nucleophilic addition reaction
• C. Electrophilic substitution reaction
• D. Electrophilic addition reaction

Explanation: Carboxylic acids react with alcohols in presence of acid as catalyst and form esters (esterification). The mechanism of esterification is (step 1) protonation of carboxylic acid, and (step 2) attack by nucleophile. Another way to understand this would be that the -OH nucleophile of a carboxylic acid is replaced by the -OR nucleophile from the deprotonated alcohol. This exchange of nucleophiles constitutes a nucleophilic substitution reaction.

Q153. Methyl cyanides, on boiling with mineral acids or alkalis yield:

• A. Acetic acid✓
• B. Formic acid
• C. Propanoic acid
• D. Butanoic acid

Explanation: In the presence of an acid, hydrolysis of nitriles like methyl cyanide gives carboxylic acids.

Q154. The amino acids which largely exist in dipolar ionic form are:

• A. Acidic amino acids
• B. Basic amino acids
• C. Beta amino acids
• D. Alpha amino acids✓

Explanation: α-amino acids exist as dipolar ions or zwitter ions.

Q155. Refer to the question below.

• A. A
• B. B✓
• C. C
• D. D

Explanation: When ammonia gas is passed through acetic acid, ammonium actate salt is formed (acid base reaction). On heating, it will be converted to acetamide eliminating water (elimination).

Q156. The reaction below gives a product called dipeptide molecule which is represented by:

• A. A
• B. B
• C. C
• D. D✓

Explanation: The following is the structure of a dipeptide.

Q157. Two or more amino acids condensed to form protein by a peptide linkage which is present between two atoms:

• A. C and C
• B. O and C
• C. C and N✓
• D. C and H

Explanation: Two or more amino acids condensed to form protein by a peptide linkage which is present between two atoms of C and N.

Q158. α-amino acids are compounds having carboxylic acid as well as amino functional groups attached to:

• A. Any H-atom in the molecule
• B. Same carbon atom✓
• C. Alternate carbon atoms
• D. Neighboring carbon atoms

Explanation: α-Amino acids are simple molecules that are made of a central C-atom, that is bound to a primary amine group NH2 and to a carboxylic group COOH.

Q159. The formula of 'Zwitter ion' is represented by:

• A. A
• B. B
• C. C
• D. D✓

Explanation: An amino acid has both a basic amine group and an acidic carboxylic acid group. There is an internal transfer of a hydrogen ion from the -COOH group to the -NH2 group to leave an ion with both a negative charge and a positive charge. This is called a zwitter on.

Q160. What is the name of amino acid where ‘R’ is a CH3 group?

• A. Glycine
• B. Lysine
• C. Aspartic acid
• D. Alanine✓

Explanation: In alanine, the alkyl chain (-R) consists of a -CH3 group.

Q161. Polyvinyl acetate (PVA) is colourless and non-toxic resin used as an adhesive and as a binder for making:

• A. Toys
• B. Gramophone recorders
• C. Compact discs
• D. Emulsion paints✓

Explanation: PVA is used in sizing agents that give greater strength to textile yarns and make paper more resistant to oils and greases. It is also employed as a component of adhesives and emulsifiers, as a water-soluble protective film, and as a starting material for the preparation of other resins.

Q162. Both ribose and deoxyribose are monosaccharides containing _ carbon atoms.

• A. 4
• B. 6
• C. 5✓
• D. 7

Explanation: Ribose and deoxyribose are 5 carbon sugars which are found in RNA and DNA. They have a furanose structure that is a 5 membered ring system with 4 carbon atoms and one oxygen atom.

Q163. Polyvinyl chloride is an example of:

• A. Condensation polymer
• B. Addition polymer✓
• C. Biopolymer
• D. Thermosetting polymer

Explanation: Polyvinyl chloride is an example of an addition polymer. It is formed by the addition polymerization of vinyl chloride monomers. In this process, the monomers simply add together without the elimination of any small moleucles.

Q164. The increased quantities of cholesterol in blood make plaque like deposits in the arteries causing:

• A. Cholera
• B. Down’s syndrome
• C. Heart attack✓
• D. Phenylketonuria

Explanation: When there are increased quantities of chloesterol in the blood, it can lead to the formation of plaque like deposits in the arteries. Over time, these deposits can narrow the arteries, restricting blood flow. If a blood clot forms and completely blocks the narrowed artery, it can result in a heart attack.

Q165. Collagen is a fibrous protein present most abundantly in:

• A. Hair
• B. Nail
• C. Tendons✓
• D. Arteries

Explanation: Collagen is most abundantly found in tendons. Tendons are fibrous connective tissues that connects muscles to bones, providing strength and facilitating movement. Collagen fibers in tendons provide structural support and contribute to their tensile strength.

Q166. Animals store glucose in the form of glycogen in:

• A. Stomach
• B. Mouth
• C. Liver and Muscles✓
• D. Small intestine

Explanation: Animals store glucose in the form of glycogen. Glycogen is a polysaccharide stored mainly in the liver and skeletal muscles. The liver plays a crucial role in regulating blood glucose levels. It stores glycogen and releases glucose into the bloodstream as needed. Muscles store glycogen to serve as an energy source during physical activity.

Q167. Aerobic decomposition of organic matter i.e. glucose by bacteria in water sediments produces?

• A. Propene
• B. Ethane
• C. Methane✓
• D. Butane

Explanation: One natural source of methane is the anaerobic decomposition of organic matter by bacteria in water sediments and in soils.

Q168. The yellowish-brown color in photochemical smog is due to the presence of:

• A. Sulphur dioxide
• B. Carbon monoxide
• C. Carbon dioxide
• D. Nitrogen dioxide✓

Explanation: The yellow colour in photochemical smog is due to the presence of nitrogen dioxide.

Q169. The wavelength ' λ' of a wave depends on the speed 'v' of the wave and its frequency 'f'. Decide which of the following is correct?

• A. f = v λ
• B. f = λ/v
• C. f = v/λ✓
• D. f = vλ2

Explanation: The equation relating frequency (f), wavelength (λ), and speed (v) of a wave is given by: v = fλ To solve for frequency (f), we can rearrange the equation as follows: f = v/λ

Q170. Name the quantity which can be measured by using the base unit kgm2s-3:

• A. Weight
• B. Pressure
• C. Power✓
• D. Work

Explanation: The following is the solution:As we know that:Power = Work / timeAnd,Work = force × distance F = maSo putting all that together:P = m × a × d / tSubstituting with their units that would make:P = kgm²s-3

Q171. The ratio of moment of inertia of two objects 'A' and 'B' is 2:3. Which one of the following is the ratio of torques of 'A' and 'B' respectively if both are being rotated with constant angular acceleration?

• A. 3:4
• B. 2:3✓
• C. 3:2
• D. 4:3

Explanation: The ratio of torques is equal to the ratio of moments of inertia when both objects are being rotated with constant angular acceleration. The moment of inertia is directly proportional to the torque applied. Since the ratio of the moment of inertia is given as 2:3, it means that the torque ratio will be the same, resulting in the ratio of 2:3.

Q172. Due to some mechanical fault, a lift falls freely from the top of a multistory building. Which of the following is the apparent weight of a man inside the lift, if the mass of the man is 80 kg while the value of 'g' is 10 ms-2?

• A. 900 N
• B. Zero✓
• C. 800 N
• D. 700 N

Explanation: If the elevator falls freely, the downward acceleration of the man in the elevator is: a = g Now, the force exerted by the floor on the man is equal to the actual weight of the man minus the net upward force on him. F = ma - mg F = mg - mg F = 0 N Hence, the force exerted by the floor on the man is zero.

Q173. Stokes' Law is given as:

• A. F = 6πηr2v
• B. F = 6πηrv✓
• C. F = 6πηrv-1
• D. F = 6π2ηr3v

Explanation: Stokes' law is a law in physics that states that the force that resists a sphere's fall in a viscous fluid is directly proportional to the velocity of the sphere, the radius of the sphere, and the viscosity of the fluid i.e. 6πηrv

Q174. The product of cross-sectional area of the pipe and the fluid speed at any point along the pipe:

• A. Remains constant✓
• B. Is zero
• C. Exponentially increases
• D. Exponentially decreases

Explanation: The product of cross-sectional area of the pipe and the velocity of the fluid at any given point along the pipe is constant and is called the continuity equation A1v1 = A2v2 According to the continuity equation, the mass flow rate of an incompressible fluid remains constant along a streamline, which implies that the product of the cross-sectional area and the fluid speed remains constant.

Q175. A small leak is developed in a large water storage tank. If the height of water above the leakage is 10 m, then find the speed of efflux through the leak:

• A. 14 m/sec✓
• B. 10 m/sec
• C. 9.8 m/sec
• D. 20 m/sec

Explanation: Height = h = 10 m Acceleration due to gravity = g = 9.8 m/s² Speed = v = ? Formula: The speed of efflux through the leak can be determined using Torricelli's law, which states that the speed of efflux of a fluid through an opening is given by the equation: v = √2gh = √2 × 9.8 × 10 v = 14 m/s

Q176. The minimum distance from the eye at which an object can be seen clearly without strain is called:

• A. Focal point
• B. Near point✓
• C. Yield point
• D. Far point

Explanation: The near point is the minimum distance from the eye at which an object can be seen clearly without strain. It is also known as the closest point of clear vision. As we age, the flexibility of the lens in the eye decreases, causing a decrease in the near point.

Q177. In the diffraction of light around an obstacle, the angle of diffraction is increased then:

• A. The wavelength of incident light waves is increased✓
• B. The wavelength of incident light waves is decreased
• C. The amplitude of the incident light wave is increased
• D. The amplitude of the incident light wave is decreased

Explanation: In the diffraction of light around an obstacle, the angle of diffraction is directly related to the wavelength of the incident light wave. When the angle of diffraction increases, it means that the light waves are bending more as they pass around the obstacle. This bending is a characteristic of diffraction and is more pronounced when the wavelength of the incident light wave is larger. Therefore, the wavelength of the incident light wave is increased, as a larger wavelength leads to a greater angle of diffraction.

Q178. An object 15 cm from a lens produces a real image 30 cm from the lens. What is the focal length of the lens?

• A. +15 cm
• B. +20 cm
• C. +10 cm✓
• D. +25 cm

Explanation: A real image can only be produced by a convex lensSo,v= +30 and u= -15The formula of the lens is 1/f=1/v-1/unow putting values1/f= 1/30-1/-151/f= 1/30+1/151/f = 3/30f= +10 cm.

Q179. What is the formula for critical angle in case of light through two media having refractive indices n1 and n2 such that n1 > n2?

• A. A
• B. B
• C. C
• D. D✓

Explanation: The critical angle (θc) in the case of light passing from a medium with a higher refractive index (n1) to a medium with a lower refractive index (n2) can be calculated using the formula: θ = sin-1(n2/n1)

Q180. For a vibrating mass-spring system, the expression of kinetic energy if x=0 is given by:

• A. A
• B. B✓
• C. C
• D. D

Explanation: In a mass-spring system, the kinetic energy is given by the formula: KE = ½ mv²In the case of a vibrating mass-spring system, the maximum displacement from equilibrium position (amplitude) is denoted by xo. At the equilibrium position (x = 0), the velocity is maximum, and it can be calculated as: v = ωxoWhere ω is the angular frequency. Now, substituting the values into the formula for kinetic energy, we have: KE = (½)m(ωxo)² = ½ mω²xo²Since k is the spring constant and: k = mω²We can rewrite the equation as: KE = ½ kxo²

Q181. The speed of sound through a gas is measured as 340 m/s at pressure P1 and temperature T1. What will be the speed of sound if the pressure of a gas is doubled but the temperature is kept constant?

• A. 342 m/s
• B. 340 m/s✓
• C. 170 m/s
• D. 680 m/s

Explanation: According to laplace equation v=√(γP/p), the pressure and velocity are directly related however if the pressure is doubled then density would also double naturally, so the speed of sound would remain the same.

Q182. The stress-strain graph deduced the following limits successively:

• A. Proportional limit, yield limit, elastic limit
• B. Yield limit, elastic limit, proportional limit
• C. Proportional limit, elastic limit, yield limit✓
• D. Elastic limit, proportional limit, yield limit

Explanation: The following limits are deduced in the order; Proportional limit, elastic limit, yield limit.

Q183. Variation of amplitude with respect to time for an oscillation object is shown in the figure. Identify the oscillation:

• A. Damped
• B. Critical
• C. Undamped✓
• D. Heavily damped

Explanation: There is no change in the oscillation's amplitude hence it is undamped.

Q184. A 4.0 m long wire is subjected to stretching force and its length increases by 40 cm. The percent elongation which the wire undergoes is:

• A. 0.10 %
• B. 40 %
• C. 10 %✓
• D. 20 %

Explanation: Given:Original length = 4mChange in length = 40 cm = 0.4 mPercentage elongation = ?Formula:To calculate the percentage elongation, we need to divide the change in length of the wire by its original length and then multiply by 100 to express it as a percentage. So,Percentage elongation = (Change in length / original length) × 100Percentage elongation = (0.4 / 4) × 100 = 0.1 × 100 = 10%

Q185. A gas sample contains three molecules each having speeds 1 ms-1, 2 ms-1, and 3 ms-1. What is the mean square speed?

• A. 14/3 m/s✓
• B. 6 m/s
• C. 2 m/s
• D. √(14/3) m/s

Explanation: To find the mean square speed of the gas sample, we need to calculate the average of the squares of the individual speeds. So,Mean square speed = (1)² + (2)² + (3)² / 3 = 1 + 4 + 9 / 3 = 14 /3Therefore, the mean square speed is 14/3ms-1.

Q186. What is the factor upon which change in internal energy of an ideal gas depends?

• A. Change in volume
• B. Change in temperature and volume
• C. Change in temperature✓
• D. Path followed to change internal energy

Explanation: The internal energy of an ideal gas depends solely on its temperature. According to the ideal gas law and the kinetic theory of gases, the internal energy of an ideal gas is directly proportional to its temperature. When the temperature of an ideal gas changes, its internal energy also changes.

Q187. What will be the mathematical form of the first law of thermodynamics for a system whose variation of volume by pressure is shown?

• A. Q = U
• B. U = W
• C. Q = U/W
• D. Q = W✓

Explanation: Since it is an isothermal process, there is no change in temperature hence the internal energy is constant. U = 0Hence, the equation will be: Q = WFor all isothermal compression or expansion of ideal gases.

Q188. For a heat engine ‘A’ the ratio of Q2 to Q1 is 2/3 while for that of heat engine ‘B’, the ratio of Q2 to Q1 is 1/3. What is the value ηA: ηB?

• A. 1:3
• B. 1:2✓
• C. 2:3
• D. 2:1

Explanation: To find the value of the efficiency ratio (ηA:ηB) between two heat engines A and B, we need to compare the ratios of their heat outputs (Q2) to their heat inputs (Q1).Given:Given that the ratio of Q2 to Q1 for engine A is ⅔ and for engine B is ⅓.Formula:We can calculate their efficiencies individually using the formula:Efficiency (η) = 1 - (Q2 / Q1)For Engine A: ηA = 1 - (⅔) = ⅓For Engine B: ηB = 1 - (⅓) = ⅔ Therefore, the efficiency ratio: ηA : ηB ⅓ : ⅔ 1 : 2The efficiency ratio of engine A to engine B is 1:2.

Q189. What is the charge stored on a 5 μF capacitor charged to a potential difference of 12 V?

• A. 60 μC✓
• B. 2.4 C
• C. 2.4 μC
• D. 60 C

Explanation: Use formula Q=CV, where C is .005 F and V is 12 V, and then convert the answer to μC by dividing it with 1000.0.005 x 12 / 1000 = 60 μC.

Q190. 12-volt battery is applied across 6-ohm resistance to have a steady flow of current. What must be the required potential difference across the same resistance to have a steady current of one ampere?

• A. 12 V
• B. 6 V✓
• C. 1 V
• D. 3 V

Explanation: To determine the potential difference required across a 6-ohm resistance to achieve a steady current of one ampere, we can use Ohm's law, which states that the current flowing through a resistor is directly proportional to the applied voltage and inversely proportional to the resistance: Use formula V=IR, where I is 1 and R is 6. V = 1 x 6 = 6 V

Q191. A solenoid is cut into two halves. Magnetic induction due to the same current in each half will be:

• A. Half of the original
• B. Double of the original
• C. Same as original✓
• D. Four times of the original

Explanation: Magnetic field due to a solenoid, B=μo n I, where n= l/N. So, if the length and number of turns become half for a solenoid, n remains the same, and thus magnetic field remains the same.

Q192. A long straight current-carrying conductor has current directed from bottom to top when held vertically. What will be the direction of magnetic field lines when observed from below the conductor?

• A. Clockwise✓
• B. Anti clockwise
• C. Vertically upward
• D. Vertically downward

Explanation: The direction of the magnetic field can be determined by the thumb rule. In your case, a straight wire is held vertically and the current passes through this wire in the upward direction. and hence, when you place your hand in the respective position and observe it from bottom it will be anticlockwise direction..

Q193. What is the output Boolean expression of logic diagram shown in figure below:

• A. A
• B. B
• C. C
• D. D✓

Explanation: The outputs of each NAND gate is given by AB and AB, making them the 2 inputs for the OR gate, so the final output X would be AB+AB.

Q194. Three resistors each having value 'R' are connected as shown in the figure. What is the equivalent resistance between 'X' and 'Y'?

• A. R
• B. R/3
• C. 3R✓
• D. R3

Explanation: The resistors are connected in series so their equivalent resistance would be the sum of resistances of all resistors. R+R+R=3R.

Q195. The diagram shows a wire, carrying a current ‘I’, placed between the poles of a magnet. In which direction does the force on the wire act?

• A. Towards the 'N' pole of the magnet
• B. Downwards✓
• C. Upwards
• D. Towards the 'S' pole of the magnet

Explanation: The force on the wire act upward. By Using Fleming's left hand rule we can find direction of force.

Q196. X-rays from a given X-ray tube operating under specified conditions have a minimum wavelength. The value of this minimum wavelength could be reduced by:

• A. Cooling the target
• B. Reducing the temperature of the filament
• C. Increasing the potential difference between the cathode and the target✓
• D. Reducing the pressure in the tube

Explanation: Increasing the potential difference between the cathode and the target can accelerate the electrons, resulting in higher energies when they interact with the target material. This increased energy can lead to X-rays with shorter wavelengths, effectively reducing the minimum wavelength.

Q197. Helium-neon lasers are used for the:

• A. Precise measurement of range finding
• B. Optical fiber communication systems
• C. Surveying for construction of tunnels✓
• D. Welding detached bone of body

Explanation: Helium-neon lasers serve in industrial alignment to determine straight lines with the laser beam in the construction of buildings, tunnels, and sewer pipes because they are inexpensive and provide continuous, visible output.

Q198. What is the type of characteristic X-ray photon whose energy is given by relation ‘hf =EM – EK’?

• A. K – alpha
• B. M – alpha
• C. K – beta✓
• D. M – beta

Explanation: When electrons from the M shell jump to occupy the hole in the K shell, the photons emitted are K-beta, and the energy emitted is hf = EM – EK

Q199. The kinetic energy of electrons by applying potential difference V1 across the x-ray tube is (KE)1, while the V2 potential difference produces kinetic energy equal to (KE)2. What, will be the value of (KE)1:(KE)2 if the ratio of potential difference V1:V2 = 2:3?

• A. 3:2
• B. 4:9
• C. 9:4
• D. 2:3✓

Explanation: Emax(KE) = hfmax = eV, V and KE are in direct relation so V:V and KE:KE ratios would be the same.

Q200. What will be the relation for the speed of electron accelerated towards the target in the X-ray tube by applying potential difference ‘V’, taking the mass of electron ‘m’ and charge on electron ‘e’?

• A. A✓
• B. B
• C. C
• D. D

Explanation: Energy gained by the electron when accelerated through a potential of V volts is E=eV This energy is completely converted to kinetic energy: E= ½ mv2 Hence ½ mv2=eV --> v2=2eV/m And hence the velocity of the electron is: √(2Ve/m).

Q201. What does CAT stand for in X-ray technology?

• A. Capacitor Amplifier Transistor
• B. Computerized Axial Tomography✓
• C. Cathode Anode Technique
• D. Current Amplification Technology

Explanation: CAT stands for "Computerized Axial Tomography." It is commonly known as CT scan (Computerized Tomography scan). CT scans use a combination of X-rays and computer technology to create detailed cross-sectional images of the body. The images produced by CT scans provide valuable diagnostic information and are used in various medical applications, such as identifying abnormalities, guiding surgical procedures, and monitoring treatment progress.

Q202. During the production of LASER, when the excited state E2 contains more atoms than the ground state E1, the state is known as:

• A. Population inversion✓
• B. Ground State
• C. Excited state
• D. Metastable state

Explanation: Population inversion refers to a condition in which the number of atoms or molecules in an excited state (such as E2) is greater than the number in the ground state (such as E1). This is a necessary condition for the amplification of light in a laser.

Q203. In a cloud chamber, the path of β-particles is:

• A. Straight, thick, short
• B. Thin, wavy, shorter
• C. Thin, wavy, longer✓
• D. Thin, straight, short

Explanation: Beta particles form thin and discontinuous tracks extending (long) in an erratic manner showing frequent deflections (wavy).

Q204. Among the three types of radioactive radiation, which has the strongest penetration power?

• A. Alpha
• B. Gamma✓
• C. Beta
• D. All have same penetration power

Explanation: Gamma rays have the strongest penetrating power, beta radiation has the 2nd strongest and alpha is the least penetrating.

Q205. The emission of alpha particles from a radioactive substance causes:

• A. Decreases in 'Z' by 4 and decreases in 'A' by 2
• B. Decreases in 'A' by 1 and 'Z' remains same
• C. Decreases in 'Z' by 1 and 'A' remains same
• D. Decreases in 'A' by 4 and decreases in 'Z' by 2✓

Explanation: The ‘A’ (atomic mass) of an alpha particle is 4 and the ‘Z’ (atomic number) is 2. Hence A and Z would decrease by 4 and 2 respectively by emission of an alpha-particle.

Q206. 10 Joules of energy is absorbed by a 10-gram mass from a radioactive source. What is the absorbed dose?

• A. 1 gray
• B. 1000 gray✓
• C. 0 gray
• D. 100 gray

Explanation: Given:Energy = E = 10 JMass = m = 10 g = 0.01 kgAbsorbed dose = ?Formula:As we know that:Absorbed dose = Energy / mass = 10 / 0.01 = 1000 gray

Q207. Isotopes are those nuclei of an element that have:

• A. Same mass number but different atomic number
• B. Same mass number as well as atomic number
• C. Different mass number as well as atomic number
• D. Same atomic number but different mass number✓

Explanation: The isotopes of an element have the same number of protons and electrons, but different numbers of neutrons. So the atomic number would be the same and the mass number or atomic mass would be different.

Q208. Which one of the following emissions takes place in the nuclear reaction? 90Th234 → 91Pa232 + _ + 20n1

• A. Alpha
• B. Gamma
• C. Beta✓
• D. Photons

Explanation: Since the atomic mass is reduced by 2 and the atomic number is reduced by 1, beta emission has taken place along with emission of two neutrons since beta particles have atomic mass and atomic number of 0 and 1 respectively.

Q209. The emission of radiation from radioactive substances is:

• A. Dependent on both temperature and pressure
• B. Independent of temperature but dependent on pressure
• C. Independent of both temperature and pressure✓
• D. Independent of pressure but dependent on temperature

Explanation: Emission of radiation from radioactive substance is a spontaneous process and it is independent of both temperature and pressure.

Q210. In a simple harmonic motion with a radius xo, the velocity of the particle at any point is:

• A. A✓
• B. B
• C. C
• D. D

Explanation: In a simple harmonic motion, the velocity of the particle at any point can be expressed as: v = ω√(xo² - x²)Where,v is the velocity of the particle,ω is the angular frequency of the motion,xo is the amplitude or maximum displacement of the motion, andx is the displacement of the particle from the equilibrium position

Q211. What is the value of universal gas constant?

• A. 8314 J mol-1K-1
• B. 83.14 J mol-1K-2
• C. 831.4 J mol-1K-1
• D. 8.314 J mol-1K-1✓

Explanation: Universal gas constant is 8.314 J mol-1K-1.

Q212. Which of the following is the proper way to study the sinusoidal waveform of voltage?

• A. Voltage is connected to ‘Y’ input and time base is switched on✓
• B. Voltage is connected to ‘X’ input and time base is switched off
• C. Voltage is connected to ‘Y’ input and time base is switched off
• D. Voltage is connected to ‘X’ input and time base is switched on

Explanation: If an AC voltage is applied across the Y-plates when the timebase is on then the sinusoidally varying voltage makes the spot move up and down around its rest position as it moves across the screen and you see a sine wave graph.

Q213. SPOT THE ERROR: In the following sentence, some segments of the sentence are underlined. Your task is to identify that underlined segment of the sentence, which contains the mistake that needs to be corrected.

• A. Option A
• B. Option B✓
• C. Option C
• D. Option D
• E. No error

Explanation: Correct is option B as 'social and economic progress, good governance' are the main verbs which are plural so 'take' should be used.

Q214. SPOT THE ERROR: In the following sentences, some segments of the sentence are underlined. Your task is to identify that underlined segment of the sentence, which contains the mistake that needs to be corrected.

• A. Let's
• B. The
• C. is
• D. to✓

Explanation: The incorrect preposition 'of' is used here. It should be replaced by 'for'. 'The bus is leaving for the last stop.'

Q215. Find errors in the following sentence:

• A. The captain, along with his team
• B. Are practising very hard✓
• C. For the
• D. Forthcoming matches.

Explanation: The captain's team is a singular term. If the noun is singular, use 'is'. If it is plural or there is more than one noun, use 'are'. For example, The cat is eating all of his food. The cats are eating all of their food. Therefore, the error lies in the statement "are practicing very hard". Instead, it should be "is practicing very hard".

Q216. 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.

Q217. SPOT THE ERROR: In the following sentences, some segments of each sentence are underlined.We were ten miles up the highway when I happened to saw this classified advertisement in the newspaper.

• A. We were
• B. Up the
• C. To saw this✓
• D. In the

Explanation: There is a grammatical error in option C: “happened to saw this”.We always use the present tense of the verb so it should be “see” not “saw”.

Q218. Choose the correct spelling of the word:

• A. Arround
• B. Arond
• C. Arund
• D. Around✓

Explanation: We are asked to select an option that is accurate. Here opt D is the right choice because the correct spelling for the given word is "Around". Therefore, Opt A, B and C are ruled out.

Q219. Identify the word or phrase that needs to be changed for the sentence to be correct.When I go into a bank, I get frighten.

• A. When
• B. A
• C. Get
• D. Frighten✓

Explanation: The key to solving these questions is reading them in your head and deciphering which part sounds odd. Frighten is clearly used wrongly over here. It could have been “Banks frighten me”, but here it should be frightened.

Q220. Identify the underlined segment in the following sentence, which contains the mistake that needs to be corrected.We wished today was sunny so that we could spend the day in the country communicating with nature.

• A. Was✓
• B. So that
• C. Could spend
• D. In the country

Explanation: Intead of 'was', 'were' should have been used. We wish today were sunny.. These phrases are never correct: I wish I was, I wish it was, he wishes he was, she wishes she was. Always remember this rule about the usage of was and were: use were with expressions that are hypothetical, wishful, imagined, desired, doubtful, and otherwise contrary to fact—that is to say, not real.