Uhs Mdcat 2016 — Solved Past Paper with Answers

Q1. His theories have been _ by recent research.

• A. Pronounced
• B. Rearmed
• C. Dammed
• D. Debunked✓

Explanation: Debunked means to prove something false or expose the hollowness of something. Thus, D is the appropriate option.

Q2. International rules _ the number of foreign entrants.

• A. Hoodwink
• B. Stipulate✓
• C. Fabricate
• D. Traverse

Explanation: Stipulate means to set conditions. Demand or specify a requirement. Hoodwink means deceiving; traverse means to cross or travel through; and fabricate means to falsify.Option B is the correct option.

Q3. The assassination of the president _ the country into war.

• A. Articulated
• B. Boomed
• C. Hobbled
• D. Precipitated✓

Explanation: Precipitated indicates forcing a condition or state to change unexpectedly and abruptly. Hence D is the correct answer because the assassination of the king led to an unexpected war.

Q4. She might be forgiven for _ beneath the pressure.

• A. Undertaking
• B. Extricating
• C. Buckling✓
• D. Resounding

Explanation: Buckle means to collapse under weight or pressure; hence, C is the correct answer.

Q5. Identify the MISTAKE in the following question:It showed that he was a man capable of looking beneath the surface of things, a man not dependent in paper manifestations.

• A. Showed
• B. Capable of
• C. Looking beneath
• D. Dependent✓

Explanation: It should be dependent upon instead of in hence D is the correct answer.

Q6. Identify the MISTAKE in the following question:When When he was a child, every time he were naughty, his foster mother used to threaten to send him to Timbuktu.

• A. He was
• B. He were✓
• C. Used to
• D. To send him

Explanation: In a past continuous tense, we use was with He, She, and It hence B is the correct answer.

Q7. Identify the MISTAKE in the following question:I was faced with alternatively of either evicting the books or else leaving them in sole, undisturbed tenancy and taking rooms elsewhere for myself.

• A. With alternatively✓
• B. Of either
• C. Or else
• D. Taking rooms

Explanation: It should be “alternate” to indicate the action of switching between states or deciding on a particular choice instead of alternatively, which indicates a different possibility; hence, A is the correct answer.

Q8. Identify the MISTAKE in the following question:I remember going to the British museum one day to read for the treatment for some slight ailment of which I had a touch-hay fever, I fancy it was.

• A. Going to
• B. Read for✓
• C. Of which
• D. I had

Explanation: Read for is used to indicate the focus whereas read up which should be the correct word is used to indicate the time spend to find out the information about something, in this case, it is the sight ailment hence B is the correct answer.

Q9. Identify the MISTAKE in the following question:The number of people in the world are rapidly increasing, rather like a gigantic snowball that not only gets bigger as it rolls but goes faster as well.

• A. Are rapidly✓
• B. Rather like a
• C. Gets bigger
• D. But goes faster

Explanation: Since “number” is singular, the phrase number of people is singular, which calls for “is” instead of “are rapid,” hence A is the correct answer. NOTE: People itself is plural, and with it, “are” should be used.

Q10. Identify the MISTAKE in the following question:It has been calculated that unless the growth is checked, there will only be enough room on Earth for people to stand by.

• A. Has been calculated
• B. Is checked
• C. There will only be
• D. Stand by✓

Explanation: The correct phrase should be "stand." The phrase "stand by" implies waiting or being ready to assist, whereas, in the context of the sentence, it is referring to standing or occupying space.

Q11. Choose the correct sentence from the following options:

• A. The government should accrue taxes for strengthen the economy of the country.
• B. The government should accrue taxes in strengthen the economy of the country
• C. The government should accrue taxes to strengthen the economy of the country.✓
• D. The government should accrue taxes by strengthen the economy of the country.

Explanation: By comparing all four sentences ,you notice there is only one difference i.e. PREPOSITION and for fact the best suited is 'to strengthen'.

Q12. Select the nearest correct meaning of the given word:STALWART

• A. Loyal✓
• B. Lazy
• C. Lacking strength
• D. High

Explanation: “Stalwart” is used as an adjective to indicate someone who is reliable and loyal; hence, A is the correct answer.

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

• A. Coward
• B. Non-cooperative
• C. Imitating
• D. Gallant✓

Explanation: “Chivalry” is used to indicate thoughtful or attentive behavior towards someone.

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

• A. Curved
• B. Traditional
• C. Formal
• D. Dashing✓

Explanation: “Rakish” is an adjective used for someone having a fashionable or stylish appearance.

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

• A. Huge✓
• B. Trivial
• C. Little
• D. Square

Explanation: “Prodigious” is an adjective for someone who is huge in size or degree.

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

• A. Colophon
• B. Concoct✓
• C. Divert
• D. Respite

Explanation: “Improvise” means to put together whatever is available to make something new.

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

• A. Anomaly✓
• B. Prototype
• C. Steward
• D. Fashion

Explanation: A paradox is when a statement is seemingly absurd and out of the ordinary, but when investigated, it proves to be true.

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

• A. Mode
• B. Token✓
• C. Quirk
• D. Bulwark

Explanation: Manifestation may be an act of showing something or a symptom of an ailment.

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

• A. Patrol✓
• B. Arcane
• C. Exhort
• D. Falter

Explanation: “Reconnoitre” to make a military observation.

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

• A. Visit✓
• B. Belch
• C. Furry
• D. Inking

Explanation: A sojourn is a temporary stay or visit.

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

• A. Wander
• B. Fonder
• C. Robust
• D. Ponder✓

Explanation: Some common synonyms of muse are meditate, ponder, and ruminate. All these words mean "to consider or examine attentively or deliberately”

Q22. Random, uncontrolled electrical activity of some cells in the brain leading to chaotic activity in both sensory and motor nerves causes patients to see and hear different strange things.

• A. Epilepsy✓
• B. Parkinson’s Disease
• C. Alzheimer’s Disease
• D. Huntington’s Disease

Explanation: Epilepsy is a neurological disorder characterized by unpredictable and recurrent seizures. Seizures occur due to sudden, abnormal electrical activity in the brain, which can lead to chaotic sensory and motor experiences.

Q23. The part of the hind brain responsible for the balance and equilibrium of the body is called:

• A. Medulla
• B. Cerebellum✓
• C. Pons
• D. Thalamus

Explanation: The cerebellum is important in maintaining body position, and balance and coordinating movements of the body.

Q24. Events of the menstrual cycle are regulated by:

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

Explanation: Gonadotrophin hormones include FSH and LH, which are released by the pituitary gland under the influence of the hypothalamus. All other hormones mentioned are plant hormones.

Q25. A decrease in FSH and an increase in estrogen cause the pituitary gland to secrete:

• A. Somatotropin
• B. Luteinizing Hormone✓
• C. Testosterone
• D. Spermatogonium

Explanation: LH works with FSH to stimulate estrogen secretion and the rupture of mature follicles to release an egg or ovum.

Q26. Transmission of Neisseria gonorrhea is best described by which of the following?

• A. Oro-fecal Route
• B. Unsafe Sex✓
• C. Vector Borne
• D. Droplet Infection

Explanation: Gonorrhea is a sexually transmitted disease that is introduced into the body through sexual contact, usually through genitals and oral contact. An infected mother can also transmit the disease to her newborn child.

Q27. Syphilis is caused by:

• A. Spirochete✓
• B. Nostoc
• C. Water blooms
• D. Cyanobacteria

Explanation: Syphilis is caused by the bacterium Treponema pallidum, which belongs to the spirochete group. Spirochetes are notable for their spiral shapes and unique motility mechanisms. This bacterial group includes pathogens known for causing various diseases, with Treponema pallidum specifically linked to syphilis. In contrast, the other options are related to cyanobacteria, which are photosynthetic bacteria not associated with sexually transmitted infections. Nostoc and cyanobacteria are both non-pathogenic in the context of syphilis, and water blooms are an environmental concern rather than a bacterial classification.

Q28. AIDS is caused by:

• A. Bacteria
• B. Virus✓
• C. Fungi
• D. Algae

Explanation: Option B is correct. Yes, AIDS is caused by a virus. The virus is called the human immunodeficiency virus (HIV). HIV is a retrovirus, which means that it carries its genetic material in the form of RNA. The RNA is reverse transcribed into DNA by the virus's reverse transcriptase enzyme. The DNA is then integrated into the DNA of the host cell, where it can be replicated and transcribed into new viral RNA. It is not caused by bacteria, fungi, or algae.

Q29. The brain is protected and enclosed in:

• A. Lumbar vertebrae
• B. Coccyx
• C. Vertebral column
• D. Cranium✓

Explanation: Cranium, which is a part of the skull is made up of 8 bones to form a brain box to protect the brain.

Q30. The longest bone in the human skeleton is:

• A. Ulna
• B. Fibula
• C. Tibia
• D. Femur✓

Explanation: The femur is the strongest and largest bone in the human body, whereas the humerus is the second-largest bone.

Q31. Hip Joint and shoulder joint are the examples of:

• A. Ball and Socket Joint✓
• B. Hinge Joint
• C. Fibrous Joint
• D. Cartilaginous Joints

Explanation: The correct answer is the 'Ball and Socket Joint.' Both the hip and shoulder joints exemplify this type of synovial joint, characterized by a spherical bone head fitting into a cup-like socket, allowing for a wide range of movement including rotation.The other options are incorrect for the following reasons:- Hinge Joint: This joint allows movement primarily in one direction, such as bending and straightening, and does not provide the extensive range of motion that ball and socket joints do.- Fibrous Joint: These joints do not allow movement, as they are tightly connected by fibers, making them unsuitable examples of joints like the hip and shoulder.- Cartilaginous Joints: These joints offer limited movement and are not as freely movable as ball and socket joints.

Q32. In the pelvic region of the human body, the sacrum is formed by the fusion of:

• A. 4 Vertebrae
• B. 5 Vertebrae✓
• C. 6 Vertebrae
• D. 3 Vertebrae

Explanation: The sacrum is formed by the fusion of five vertebrae (S1-S5) in the pelvic region of the human body.

Q33. Each muscle fiber is surrounded by a modified cell membrane called:

• A. Sarcolemma✓
• B. Sarcoplasmic reticulum
• C. Sarcomere
• D. Myofilament

Explanation: The correct answer is the sarcolemma, which is the modified cell membrane surrounding each muscle fiber. It is essential for maintaining the structural integrity of the muscle cell and plays a vital role in the transmission of action potentials and muscle contractions. The other options, such as the sarcoplasmic reticulum, sarcomere, and myofilament, refer to different components within the muscle fiber that contribute to its function but do not serve as the membrane surrounding the fiber.

Q34. _ hormone is antagonistic to insulin and causes an increase in blood glucose levels.

• A. Glucagon✓
• B. Calcitonin
• C. Nor-epinephrine
• D. Thyroxine

Explanation: Beta cells of the islets of Langerhans secrete insulin, which lowers blood glucose by increasing uptake and storage in cells.

Q35. Beta cells of islets of Langerhans produce _ hormone.

• A. Glucagon
• B. Pancreatic juice
• C. Insulin✓
• D. Parathormone

Explanation: Beta cells of the islets of Langerhans secrete insulin, which lowers blood glucose by increasing uptake and storage in cells.

Q36. The central portion of the adrenal gland (the adrenal medulla) produces _ hormone.

• A. Aldosterone
• B. Epinephrine✓
• C. Androgen
• D. Corticosterone

Explanation: The adrenal medulla produces catecholamines, epinephrine, and norepinephrine.

Q37. _Hormones called fight or flight hormones prepare an organism to face stressful situations.

• A. Adrenaline, Aldosterone
• B. Epinephrine, Nor-epinephrine✓
• C. Cortisone, Oxytocin
• D. Thyroxine, Nor-epinephrine

Explanation: Epinephrine and norepinephrine stimulate the effects of the sympathetic system (fight or flight).

Q38. B-cells release antibodies in blood plasma, tissue fluid, and lymph. This kind of immune response is called

• A. cell-mediated response
• B. Humoral Response✓
• C. Active Response
• D. Compound Response

Explanation: Immunity provided by the AB secreted in the circulatory system by B cells is termed humoral immunity.

Q39. The type of immunity in which antibodies are passed from one individual to another is called

• A. Passive Immunity✓
• B. Artificial Active Immunity
• C. Natural Active Immunity
• D. Humoral Immunity

Explanation: Passive immunity develops after you receive antibodies from someone or somewhere else. This type of immunity is short-lived, and it doesn’t cause your immune system to recognize the pathogen in the future.

Q40. To combat the active infections of tetanus, rabies, and snakes, the _ method of immunization is used.

• A. Active
• B. Humoral
• C. Active Artificial
• D. Passive✓

Explanation: Passive immunity can also be transferred artificially by introducing antibodies with the help of vaccinations derived from animals or human beings who are already immune to that disease.

Q41. 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

Q42. Variable amino acid sequences in antibody molecules are found in:

• A. Both light chains only
• B. Both heavy chains only
• C. One heavy and one light chain
• D. Both heavy and light chains✓

Explanation: The amino acid sequence in the tips of the “Y” varies greatly among different antibodies. This variable region, composed of 110–130 amino acids, gives the antibody its specificity.

Q43. Each _ consists of a light-gathering antenna complex and reaction center

• A. Chlorophyll
• B. Photosystem✓
• C. Photon
• D. Electron

Explanation: Photosystem is the correct option because it refers to the functional unit in the chloroplasts of plants and cyanobacteria where the process of photosynthesis takes place. It consists of a light-gathering antenna complex that captures photons and a reaction center where the captured light energy is converted into chemical energy through the transfer of electrons.

Q44. Photosystem I have chlorophyll, a group of molecules that absorb maximum light of:

• A. 680 nm
• B. 780 nm
• C. 700 nm✓
• D. 580 nm

Explanation: There are two photosystems: PSI and PSII. These are named in order of their discovery. Photosystem I has chlorophyll, a molecule that absorbs the maximum light at 700nm. Whereas PSII absorbs the maximum light at 680nm.

Q45. The cyclic flow of C4 photosynthesis produces:

• A. ATP and CO2
• B. ATP✓
• C. Only CO2
• D. Only Oxygen

Explanation: Linear electron flow (LEF) in photosynthesis produces both ATP and NADPH, and the cyclic electron flow (CEF) around photosystem I has been shown to produce only ATP.

Q46. Immediate product formed after CO2Fixation in the Calvin Cycle is:

• A. Unstable 6-carbon compound✓
• B. Unstable 5-carbon compound
• C. Unstable 4-carbon compound
• D. Unstable 3-carbon compound

Explanation: The correct option is A, as the first unstable product formed after CO2 fixation in the Calvin Cycle is the 6-carbon compound 3-phosphoglycerate (3-PGA).

Q47. Functional group of chlorophyll a:

• A. —CH3✓
• B. —CHO
• C. —COOH
• D. —OH

Explanation: Chlorophyll A is a bluish-green pigment that is soluble in organic solvents like acetone and alcohol. It’s molecular formula is C55H72O5N4Mg. It is made up of a squarish tetrapyrrolic ring known as the head and a phytol alcohol known as the tail.

Q48. The modified plasmid or phage DNA is called:

• A. lone DNA
• B. Recombinant DNA✓
• C. cDNA
• D. rDNA

Explanation: Recombination is the process through which a new gene is inserted into a bacterial DNA "The plasmid". Then the restriction enzyme cuts, it leaves a "Sticky end" which helps a new gene to attach at that point. The new attached gene gives rise to several copies, the resulting copies are referred to as ‘Recombinant DNAs’. Since it’s a combination of genetic material from two different species.

Q49. The rapid exchange of materials through carrier proteins across the plasma membrane is called

• A. Passive Diffusion
• B. Active Transport
• C. Endocytosis
• D. Facilitated Diffusion✓

Explanation: Facilitated diffusion, a type of passive transport is best known and defined as the type diffusion of large molecules via specific transmembrane carrier proteins. Only type of passive diffusion done via carrier proteins.

Q50. The inner membrane of mitochondria form extensive infoldings called:

• A. Cristae✓
• B. Cisternae
• C. Lamella
• D. Bifidae

Explanation: Mitochondria are a double-membranous structure with an outer membrane and an inner membrane.

Q51. Which one of the following organelle is found in both prokaryotic and eukaryotic cells?

• A. Centriole
• B. Endoplasmic Reticulum
• C. Nucleus
• D. Ribosome✓

Explanation: Ribosomes are the correct answer because they are non-membranous organelles that synthesize proteins and are found in both prokaryotic and eukaryotic cells. In contrast, centrioles, the endoplasmic reticulum, and the nucleus are membrane-bound organelles that are characteristic of eukaryotic cells and are absent in prokaryotic cells.

Q52. The compounds which, on hydrolysis, yield polyhydroxy aldehyde or ketone subunits are:

• A. Lipids
• B. Polynucleotides
• C. Proteins
• D. Carbohydrates✓

Explanation: The correct answer is Carbohydrates. Carbohydrates consist of carbon, hydrogen, and oxygen and are the only biomolecules that, upon hydrolysis, yield polyhydroxy aldehyde or ketone subunits such as monosaccharides like glucose and fructose. Lipids, polynucleotides, and proteins do not yield such subunits when hydrolyzed. Lipids break down into glycerol and fatty acids, polynucleotides into nucleotides, and proteins into amino acids.

Q53. Which one of the following is the formula structure of D (α) glucose?

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

Explanation: This structure shows a six-membered ring (pyranose form) with the OH group on the anomeric carbon (carbon-1) pointing down relative to the CH₂OH group on carbon-5. In D-glucose, this “down” position indicates the α-anomer. The rest of the OH groups follow the correct D-glucose configuration (C-2 OH down, C-3 OH up, C-4 OH down when drawn in Haworth projection). This matches the definition of D(α)-glucose.

Q54. Secondary structure of protein is found in:

• A. Trypsin
• B. Insulin
• C. Keratin✓
• D. Glucagon

Explanation: Keratin is the correct answer because it is a fibrous protein known for its strong secondary structure, primarily alpha-helices, which provide mechanical strength and resilience. The other options, such as trypsin, insulin, and glucagon, are proteins or peptides that do not predominantly exhibit or rely on secondary structures for their primary functions. These molecules are more influenced by their tertiary and quaternary structures, which dictate their biological roles and stability.

Q55. Waxes are formed by the combination of fatty acids with:

• A. Alcohol✓
• B. Glycerol
• C. Serine
• D. Cysteine

Explanation: A wax is a simple lipid, which is an ester of a long-chain alcohol and a fatty acid

Q56. Phosphodiester bond is:

• A. P-O-C-P-O-C
• B. C-O-P-O-C✓
• C. C-O-P
• D. C-C-O-P

Explanation: The correct answer is Option B: C-O-P-O-C. A phosphodiester bond forms the backbone of DNA and RNA molecules by linking the 5' carbon of one sugar molecule to the 3' carbon of the next sugar, with a phosphate group in between. This bond is crucial for the structural integrity of nucleic acids. Option A is incorrect as it suggests a direct linkage between phosphorus atoms and carbons that does not exist in phosphodiester bonds. Option C is partially correct but incomplete, as it fails to demonstrate the full linkage across two sugar molecules. Option D incorrectly suggests a carbon-carbon linkage, which is not a feature of phosphodiester bonds.

Q57. An enzyme requires Mg2+to catalyze the substrate. The Mg2+is best identified as:

• A. Prosthetic group
• B. Activator✓
• C. Co-enzyme
• D. Inhibitor

Explanation: Mg2+ is an essential inorganic activator for enzyme phosphatase, not to be confused with the prosthetic group.

Q58. This figure represents a _ inhibitor.

• A. Non-competitive✓
• B. Competitive
• C. Irreversible
• D. Isosteric

Explanation: In noncompetitive inhibition, the inhibitor binds at an allosteric site separate from the active site of substrate binding. Thus, in noncompetitive inhibition, the inhibitor can bind its target enzyme regardless of the presence of a bound substrate.

Q59. According to _ model, the active site of enzyme is modified as the substrate interacts with enzyme.

• A. Induced fit✓
• B. Lock and Key
• C. Emil Fischer
• D. Fluid Mosaic

Explanation: According to the induced fit model, when a substrate combines with an enzyme, it induces changes in the enzyme structure. The change in structure enables the enzyme to perform its catalytic activity more efficiently.

Q60. Which one of the following graphs shows how the rate of reaction of pepsin is affected by pH?

• A. Graph A
• B. Graph B
• C. Graph C
• D. Graph D✓

Explanation: Every enzyme works best at its optimum pH. Pepsin's optimum pH is 2. Graph D shows the correct optimal pH peak near pH 2, and it is the correct option. Other options shows optimal pH peak at different pH other than 2.

Q61. All viruses can reproduce only within living organisms, so they are known as:

• A. Ectoparasites
• B. Endoparasites
• C. Obligative Intracellular Parasites✓
• D. Facultative Intracellular Parasites

Explanation: Intracellular obligate parasites depend on the host not only for nutrition but also for reproduction. These organisms infect the host cell and utilize the internal cellular machinery of the host to replicate themselves.

Q62. Many bacteria are motile due to the presence of:

• A. Flagella✓
• B. Pili
• C. Cilia
• D. Microtubules

Explanation: The correct answer is Flagella. Flagella are specialized structures that provide motility to bacteria by rotating like propellers, allowing them to move towards or away from various stimuli. This is a key feature distinguishing motile bacteria from non-motile ones. Other structures like Pili are involved in adhesion rather than movement, Cilia are not present in bacteria, and Microtubules are eukaryotic cell structures unrelated to bacterial motility.

Q63. _ is an invagination of cell membrane which helps in cell division.

• A. Fimbriae
• B. Nucleoid
• C. Mesosome✓
• D. Endospore

Explanation: Mesosomes are invaginations or infoldings of the cell. membrane in certain bacterial cells. They were once thought to play a role in processes like DNA replication and cell division.

Q64. _ is the yeast that grows in the mucous membrane of the mouth or vagina.

• A. Candida albicans✓
• B. Saccharomyces cerevisiae
• C. Aspergillus fumigatus
• D. Aspergillus flavus

Explanation: Candida albicans, an opportunistic pathogenic yeast is a common member of the human mouth and vaginal flora.

Q65. Taenia is an endoparasite of human, pig and cattle which belongs to thethatpigs,humans phylum.

• A. Cnidaria
• B. Aschelminthes
• C. Annelida
• D. Platyhelminthes✓

Explanation: Intracellular parasites are endoparasites that live within the cell of the host.

Q66. The body of _ consists of segments called proglottis, which contain mainly sexual organs.

• A. Planaria
• B. Ascaris
• C. Fasciola
• D. Tapeworm✓

Explanation: Proglottid can be defined as each segment in the strobils of a tapeworm containing a complete sexually mature reproductive system.

Q67. _ is a common parasite of the intestine of human and pigshumans that belongs to the phylum nematode.

• A. Taenia solanum
• B. Schistosoma
• C. Ascaris lumbriocoides✓
• D. Fasciola hepatica

Explanation: Ascaris belongs to phylum Nematode. It is a parasitic worm. It causes ascariasis disease.

Q68. In radial symmetry, all body parts are arranged around the central axis. Radial symmetry represents _ mode of life.

• A. Sessile✓
• B. Streamlined
• C. Active
• D. Parasitic

Explanation: Radial symmetry is a basic body plane in which the organism can be divided into similar halves by passing a plane at any angle along a central axis. It is characteristic of sessile and bottom-dwelling animals, such as the sea anemone and starfish.

Q69. Pseudo-coelomates have a body cavity but it is not true coelom. Which one of the following is included in the group?

• A. Planaria
• B. Earthworm
• C. Tapeworm
• D. Ascaris✓

Explanation: Ascaris lumbricoides is an intestinal parasite of man that is included in pseudo-coelomates.

Q70. Digestion of _ starts in oral cavity due to the action of enzyme present in :

• A. Starch.✓
• B. Fatty Acids
• C. Cellulose
• D. Polypeptides

Explanation: Starch digestion begins in the mouth with the help of salivary amylase.

Q71. Food enters from stomach into small intestine through:

• A. Pyloric sphincter✓
• B. Semilunar valve
• C. Cardiac sphincter
• D. Diaphragm

Explanation: The pyloric sphincter controls the passage of food from the stomach to the small intestine .

Q72. _ are the parts of a gastric gland that produce hydrochloric acid.

• A. Parietal Cells✓
• B. Goblet Cells
• C. Chief Cells
• D. Zymogen Cells

Explanation: Parietal cells (also known as oxyntic cells) are epithelial cells in the stomach that secrete hydrochloric acid (HCl).

Q73. Protein components of food are digested by the enzymatic secretion of:

• A. Goblet Cells
• B. Zymogen Cells✓
• C. Parietal Cells
• D. Oxyntic Cells

Explanation: Zymogen cells secrete inactive enzymes like pepsinogen, which help in protein digestion.

Q74. The digestive system consists of different layers; the innermost is known as:

• A. Submucosa
• B. Mucosa✓
• C. Muscularis
• D. Serosa

Explanation: Mucosa is the innermost layer of the digestive tract and is responsible for secretion and absorption.

Q75. In human the closed sac which surrounds the heart is:

• A. Endocardium
• B. Pericardium✓
• C. Myocardium
• D. Epicardium

Explanation: Yes, the closed sac which surrounds the heart in humans is the pericardium. The pericardium is a double-walled sac that surrounds the heart and the roots of the major blood vessels that extend from the heart. The pericardium is made up of two layers: the fibrous pericardium and the serous pericardium.The fibrous pericardium is the outermost layer of the pericardium. It is a tough, fibrous sac that protects the heart and helps to keep it in place.The serous pericardium is the innermost layer of the pericardium. It is a thin, delicate sac that is made up of two layers: the parietal pericardium and the visceral pericardium.The parietal pericardium is attached to the fibrous pericardium. Whereas, the visceral pericardium is attached to the surface of the heart. The space between the parietal pericardium and the visceral pericardium is called the pericardial cavity. The pericardial cavity contains a small amount of fluid that helps to lubricate the heart and allow it to move freely.

Q76. Chordae tendinae are the fibrous cords attached with:

• A. Cardiac end of stomach valve
• B. Pyloric sphincter of stomach
• C. Tricuspid valve of heart✓
• D. Eyelid

Explanation: The chordae tendineae are fibrous cords that attach the flaps of the tricuspid valve to the papillary muscles in the right ventricle of the heart. They help to keep the flaps of the valve closed during ventricular contraction, preventing blood from flowing back into the right atrium. The chordae tendineae are made up of collagen and elastin fibers. They are strong and elastic, which allows them to stretch and contract as the heart beats. The chordae tendineae are important for the proper functioning of the tricuspid valve. If the chordae tendineae are damaged or weakened, the flaps of the valve may not close properly, which can lead to blood flow back into the right atrium. This can cause a condition called tricuspid regurgitation.

Q77. Bicuspid valve controls the flow of blood front:

• A. Right atrium to right ventricle
• B. Left ventricle to aorta
• C. Right ventricle to pulmonary artery
• D. Left atrium to left ventricle✓

Explanation: The bicuspid valve (also known as the mitral valve) controls the flow of blood from the left atrium to the left ventricle. The bicuspid valve has two flaps that open and close to allow blood to flow in one direction only. When the left atrium contracts, it pushes blood against the flaps of the bicuspid valve. The flaps open, allowing blood to flow from the left atrium to the left ventricle. When the left ventricle contracts, it pushes blood against the flaps of the bicuspid valve. The flaps close, preventing blood from flowing back into the left atrium. The bicuspid valve is a very important valve that helps to ensure that blood flows in the correct direction through the heart. Without the bicuspid valve, blood would flow back into the left atrium from the left ventricle, which could cause serious health problems.

Q78. Carbaminohaemoglobin (10–20%) is formed when CO2 combines with:

• A. Amino group of haemoglobin✓
• B. Iron is part of haemoglobin
• C. heme portion of haemoglobin
• D. Plasma proteins

Explanation: Carbaminohemoglobin is a stable complex of carbon dioxide and hemoglobin that forms in red blood cells upon contact with carbon dioxide.

Q79. Breathing consists of:

• A. Four phases
• B. One phase
• C. Three phases
• D. Two phases✓

Explanation: Breathing is mechanical process consisting of two phases i.e.inspiration and expiration.

Q80. Bowman’s capsule continues in an extensively convoluted portion known as:

• A. Peritubular capillaries
• B. Proximal convoluted tubules✓
• C. Efferent arterioles
• D. Afferent arterioles

Explanation: Bowman’s capsule, a cup-like sac surrounding the glomerulus, is part of the nephron.

Q81. Restriction endonucleases cleave the _ of duplex DNA.

• A. Nitrogenous base
• B. Base sugar
• C. Phosphodiester bond✓
• D. Hydrogen bond

Explanation: The restriction endonucleases cuts the two strands of the double helix at specific point in the sugar phosphate backbone of DNA, it breaks phosphodiester bonds between the phosphate and the pentose sugar.

Q82. The enzyme that is responsible for the formation of bonds between two double-stranded DNA fragments is:

• A. Endonuclease
• B. Urease
• C. Ligase✓
• D. Helicase

Explanation: Ligase is also known as molecular glue, responsible for the binding of two molecules, using ATP. DNA ligase is an example of a ligase responsible for the binding of two DNA strands together.

Q83. The organisms of the third trophic level are:

• A. Primary consumer
• B. Primary producer
• C. Tertiary consumer
• D. Secondary consumer✓

Explanation: Secondary consumers belong to trophic level three, they feed on primary consumers.

Q84. The ultimate source of energy in an ecosystem is

• A. Photosynthesis
• B. Sun✓
• C. Plants
• D. Water

Explanation: Sun is the ultimate source of energy because it is the source of most of the energies on Earth. It provides solar energy, it is responsible for photosynthesis in plants and also provides vitamin D to humans.

Q85. All the food chains and food webs begin with:

• A. Detritus
• B. Herbivores
• C. Green plants✓
• D. Omnivores

Explanation: The living part of the food chain always begins with plant life, as plants are the only organisms that get their energy from a nonliving source, Sun. We know that the Sun is the ultimate source of energy because it does not depend on anything else.

Q86. The change from bare rock or open area is rapid, especially in the initial stages and follows a series of recognizable and hence predictable stages. This process is called

• A. Pioneers
• B. Xerosere
• C. Succession✓
• D. Secondary succession

Explanation: A broad definition of succession states: ‘Ecological succession is the process by which the mix of species and habitat in an area changes over time. Gradually, these communities replace one another until a “climax community” is reached.’ (via news.uchicago.edu) This fits the description provided in the question hence it’s the correct option.

Q87. The decline in the thickness of the ozone layer is caused by:

• A. Increasing levels of nitrogen oxide
• B. Decreasing level of O2
• C. Decreasing level of CFCs
• D. Increasing levels of CFCs✓

Explanation: An increase in CFC gas is responsible for the deterioration of the ozone layer. ‘When chlorofluorocarbons (CFC) drift upwards towards the stratosphere, they come in contact with the Ozone layer. This leads to a chemical reaction where the CFC molecules are broken up by ultraviolet radiation, releasing chlorine atoms, which are able to destroy ozone molecules.’ (via. byjus.com)

Q88. Which one of the following is considered strong evidence of evolution?

• A. Embryology Record
• B. Molecular Record
• C. Biochemical Record
• D. Fossil Record✓

Explanation: Fossils are important evidence for evolution because they show that life on earth was once different from life found on earth today.

Q89. Structures found in different species that are believed to have a common evolutionary origin are called:

• A. Homologous✓
• B. Analogous
• C. Vestigial
• D. Fossilized

Explanation: Homologous organs can be defined as the organs of different animals that are similar in structure but perform different functions. Homologous organisms share a common ancestry. Hence, the correct option is A.

Q90. Which one of the following is a sex-linked trait in humans?

• A. Tongue rolling
• B. Baldness
• C. Haemophilia✓
• D. Skin color

Explanation: Hemophilia is X-linked recessive, affecting mostly males. Tongue rolling and skin color are autosomal traits, while baldness is sex-influenced, not sex-linked.

Q91. A character determined by three alleles is:

• A. Human skin color
• B. Human eye color
• C. Human blood group✓
• D. Human Rh factor

Explanation: The correct answer is the ABO blood group system, which is determined by three alleles: IA, IB, and i. These alleles combine to form four possible blood types: A, B, AB, and O. The presence of three alleles makes this a multiple allelic system.In contrast, human skin color and eye color are polygenic traits influenced by multiple genes, each with several alleles, rather than being determined by just three alleles. The Rh factor is a simple trait determined by two alleles, making it different from the ABO system.

Q92. The total number of genes in a population is called:

• A. Gene pool✓
• B. Genome
• C. Allele pool
• D. Genomic Library

Explanation: The correct answer is the gene pool. It represents all the genetic material available in a population and is essential for understanding genetic variation and evolution. The genome describes the full genetic content of an individual, not a population. An allele pool focuses on different forms of a specific gene, which is a component of the gene pool but not synonymous with it. A genomic library is a tool used in genetic research, representing cloned DNA fragments, and does not pertain to genetic diversity within a population.

Q93. _ is the branch of Biology used for the identification and interpretation of fossils.

• A. Evolution
• B. Paleontology✓
• C. Zoogeography
• D. Biodiversity

Explanation: Palaeontology is the study of prehistoric life on Earth using geological methods such as studying preserved remains of an organism in a sediment, also known as fossil. Hence this option is correct.

Q94. Out of the given options, choose the one which shows the structures found only in plants

• A. Vacuole, Chloroplast, and ribosomes
• B. Chloroplasts, Microtubules, and peroxisomes
• C. Chloroplast, Cell Wall, and vacuole✓
• D. Chloroplast, Cell Wall, Mitochondria

Explanation: All mentioned organelles are absent in animal cells and are only present in plant cells hence this option is correct.

Q95. Presence of large central vacuole is the characteristic of:

• A. Prokaryotes
• B. Protists
• C. Fungi
• D. Plants✓

Explanation: The correct answer is Plants because mature plant cells contain a large central vacuole, which is vital for various functions, including the storage of nutrients and waste products, as well as maintaining turgor pressure to support the plant structure. In contrast, Prokaryotes (Option A) are simpler cells without membrane-bound organelles, so they do not have vacuoles. Protists (Option B) may possess vacuoles, but these are not typically large central vacuoles as seen in plants. Fungi (Option C) have smaller vacuoles and do not exhibit the same large central vacuole characteristic.

Q96. The basic structure of the plasma membrane is provided by:

• A. Proteins
• B. Cholesterols
• C. Cytoskeleton
• D. Phospholipids✓

Explanation: The fundamental structure of the membrane is the phospholipid bilayer, which forms a stable barrier between two aqueous compartments.

Q97. The organelles involved in the detoxification of drugs and poisons in the liver cells are:

• A. Smooth Endoplasmic Reticulum✓
• B. Rough Endoplasmic Reticulum
• C. Golgi Apparatus
• D. Lysosomes

Explanation: Smooth endoplasmic reticulum in liver cells of vertebrates helps in detoxifying poisons and drugs. It contains enzymes that catalyze a number of reactions.

Q98. Down’s syndrome is characterized by _ at chromosome 21.

• A. Trisomy✓
• B. Monosomy
• C. Polysomy
• D. Disomy

Explanation: In Down syndrome, there is an additional copy of chromosome 21, resulting in three copies instead of the normal two. Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome 21.

Q99. Which of the following is an example of autosomal non-disjunction?

• A. Turner’s Syndrome
• B. Jacob’s Syndrome
• C. Metastasis
• D. Down’s syndrome✓

Explanation: Non-disjunction causes an abnormal number of chromosomes in all cells, called aneuploidy, or in some cells, called mosaicism. Some of the important examples are Down's syndrome and trisomy of autosomes, i.e., chromosome 21. It contains one extra chromosome 21.

Q100. Infertility, short height, a webbed neck, and a low hairline are symptoms of _ syndrome.

• A. Turner’s✓
• B. Down’s
• C. Edward’s
• D. Patau’s

Explanation: Turner syndrome, a condition that affects only females, results when one of the X chromosomes (sex chromosomes) is missing or partially missing. Turner syndrome can cause a variety of medical and developmental problems, including short height, failure of the ovaries to develop and heart defects.

Q101. The concentration of sodium ions in body fluids is controlled by the hormone

• A. Renin
• B. Aldosterone✓
• C. Angiotensin
• D. CPK

Explanation: Aldosterone (ALD) is a hormone that helps regulate your blood pressure by managing the levels of sodium (salt) and potassium in your blood and impacting blood volume. Released by the adrenal glands.

Q102. A hormone released from the posterior pituitary lobe acts to actively transport water from filtrate collecting tubules back to the kidney. It is shown as:

• A. Renin
• B. Antidiuretic hormone✓
• C. Angiotensin
• D. Growth Factor

Explanation: The antidiuretic hormone, also known as vasopressin, is produced in the hypothalamus and stored in the posterior pituitary gland. It can cause the kidney to release less water, decreasing the amount of urine produced. A deficiency of ADH can cause diabetes insipidus

Q103. The removal of metabolic waste from the blood is called

• A. Thermoregulation
• B. Osmoregulation
• C. Kidney Failure
• D. Excretion✓

Explanation: Excretion is the process why which metabolic waste is removed from our body its includes the removal of waste through kidney,skin or lungs..Waste products produced in our body during various metabolic processes are called excreted, and the process of there removal is named excretion.

Q104. Highly toxic nitrogenous excretory products are:

• A. CO2
• B. Uric Acid
• C. Urea
• D. Ammonia✓

Explanation: The table above shows that ammonia requires the highest percentage of water for excretion, which shows that ammonia contains the highest percentage of nitrogen. Ammonia is a highly toxic nitrogenous excretory product that is produced in the breakdown of proteins and amino acids. It must be excreted rapidly to avoid toxicity.

Q105. Humans have a homeostatic thermostat present in a specified portion of the brain that is:

• A. Lateral ventricle
• B. Thalamus
• C. Spinal cord
• D. Hypothalamus✓

Explanation: The hypothalamus is a section of the brain that controls thermoregulation. If hypothalamus senses internal temperature growing too hot or too cold, it will automatically send signals to the skin, glands,muscles,and organs, which will respond in various ways to return temperature to tropical range

Q106. The disease in which the death of a small number of cells in the basal ganglia leads to an inability to select and initiate patterns of movement is known as:

• A. Fever
• B. Alzheimer’s Disease
• C. Epilepsy
• D. Parkinson’s Disease✓

Explanation: Parkinson's disease is caused by the loss of brain cells; these cells are associated with the release of dopamine. It causes shaking, stiffness, and difficulty balancing. Parkinson's disease is known as the most notorious disease of the basal ganglia (a group of structures linked to the thalamus at the base of the brain). It is a degenerative disease.

Q107. A neurological disorder characterized by a decline in brain function is _. Its symptoms are similar to those of diseases that cause dementia.

• A. Parkinson’s Disease
• B. Epilepsy
• C. Alzheimer’s Disease✓
• D. Diabetes

Explanation: Alzheimer's disease is a neurological disorder characterized by a progressive decline in cognitive function, memory loss, and difficulty in daily activities, leading to dementia.

Q108. A discharge by the brain that causes chaotic activity in motor and sensory areas is:

• A. Meningitis
• B. Alzheimer's Disease
• C. Epilepsy✓
• D. Parkinson's sensory

Explanation: A key point in this MCQ is chaotic activity in the motor AND SENSORY areas, which gives a meaning to seizures. Seizures are the symptoms of epilepsy caused by the excessive discharge of neurons in the brain.

Q109. It is a hormone that regulates our diurnal rhythms.

• A. FSH
• B. MSH
• C. Melatonin✓
• D. Prolactin

Explanation: Melatonin is a hormone secreted by the pineal gland that helps regulate our diurnal (daily) rhythms, including sleep-wake cycles.

Q110. Which one of the following is the structural formula of proline?

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

Explanation: The formula of proline is C9H5NO2 and its IUPAC name is pyrrolidine-2-carboxylic acid. It's the only amino acid where the side chain is connected to the protein backbone twice, forming a ring structure.

Q111. In the formation of the Zwitter ion, which one of the following donates the proton?

• A. COOH✓
• B. NH2
• C. CH2COO-
• D. OH-

Explanation: Zwitter ions are ions with two functional groups; they contain both positive and negative charges and are considered neutral. They are also called inner salts. One common example of a zwitter ion is protein, where a proton is transferred from COOH to NH2 but the charge of COO- and NH3 will be balanced internally.

Q112. What is the name of the given structural formula?

• A. Aspartic Acid
• B. Asparagine
• C. Adipic Acid
• D. Glutamic Acid✓

Explanation: KEY POINTS GIVEN STRUCTURE HAS 5 CARBONSGIVEN STRUCTURE IS AN AMINO ACID SO IT ELIMINATES THE CHANCES OF OPTION CGlutamic acid has formula C5H9NO4

Q113. Which one of the following is the simplest amino acid?

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

Explanation: Glycine is the simplest amino acid because it has the smallest side chain, which consists of just a single hydrogen atom. This simplicity makes it the most basic building block of proteins.

Q114. Which one of the following polymers is called Nylon 6,6?

• A. Polyester
• B. Polyvinyl chloride
• C. Polyamide✓
• D. Polyvinyl acetate

Explanation: Nylon is a type of polyamide fiber; it is named polyamide due to the amide groups. Nylon 66 is made by condensation of hexamethylenediamine and adipic acid, both 6,6 carbons.

Q115. Which one of the following is the exact composition of carbohydrates?

• A. Carbon and Hydrogen
• B. Carbon and Oxygen
• C. Carbon, Hydrogen and Oxygen✓
• D. Hydrogen and Oxygen

Explanation: Carbohydrates are organic compounds composed of carbon, hydrogen, and oxygen atoms in specific ratios. The general formula for carbohydrates is (CH2O)n, where "n" represents the number of repeating units. Option C is correct because it includes all three elements present in carbohydrates.

Q116. Which one of the following nitrogen bases is not present in DNA?

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

Explanation: Uracil is a nitrogen base present in RNA but not in DNA. In DNA, the nitrogen bases are adenine (A), guanine (G), cytosine (C), and thymine (T). Uracil replaces thymine in RNA.

Q117. The percentage of cellulose in woody parts of trees is

• A. 50%✓
• B. 10%
• C. 30%
• D. 100%

Explanation: Nearly 45% of woody trees contain cellulose. While 25% of woody plants are lignin. In plants, cellulose plays an important role in keeping plant cell walls stable.

Q118. Choose the right molecule.

• A. CH3
• B. CO
• C. H2O
• D. NH3✓

Explanation: Key points Valence shell: the larger atom has 5 electrons so it means it belongs to group VA A smaller atom has only one valence electron so it means it belongs to group IA The molecules in product have four atoms

Q119. Indicate the name of of structure given below.

• A. Nylon 6,6
• B. Adipic Acid
• C. PVA
• D. Polyester✓

Explanation: It is a polymer of 1.3-propanediol and terephthalic acid. The reactants are alcohol and acid, which shows the formation of an ester bond. Terephthalic acid does have an aromatic structure.

Q120. In a laboratory experiment, when an unknown compound was added to a test tube containing iodine, the color of the tube became intense blue. What could be the unknown compound?

• A. Cellulose
• B. Raffinose
• C. Ribose
• D. Starch✓

Explanation: The intense blue color formed when an unknown compound is added to iodine indicates the formation of a starch-iodine complex. Starch is known to give this characteristic blue color with iodine due to the formation of a helical inclusion complex.

Q121. Ozone concentration is measured in:

• A. Debye units
• B. Dupont units
• C. Debacle units
• D. Dobson units✓

Explanation: The Dobson unit is the correct unit for measuring ozone concentration. It is named after G.M.B. Dobson, who was a British meteorologist. Dobson units represent the thickness of an ozone layer if it were condensed into a single layer at standard temperature and pressure (STP).

Q122. The gas that is mainly produced in landfills from the waste is:

• A. CH4✓
• B. CO2
• C. SO2
• D. Cl2

Explanation: Methane is the gas released from marshy and landfill areas. Methane is released as waste material by bacteria.In landfill areas, gases are produced when bacteria break down organic waste. it includes mainly CO2 and methane, and traces of some other gases like nitrogen, Oxygen and ammonia, but the byproduct in that case is always methane.

Q123. The substance for the separation of isotopes is first converted into the:

• A. Neutral state
• B. Free state
• C. Vapour state✓
• D. Charged state

Explanation: Mass spectrometry is one of the most precise ways of differentiating isotopes on the bases of charge-to-mass ratio It includes five major STEPS IN the following sequence: (1) Vaporization: the sample of the element is vaporized. (2) Ionization-positive ions are obtained from the vapour (3) Acceleration: the positive ions are accelerated by an electric field (4) Deflections are deflected by magnetic fields. (5) Detection-ions are detected and the record is made

Q124. The number of moles of CO2 that contain 8g of oxygen is:

• A. 0.75
• B. 1.50
• C. 0.25✓
• D. 1.00

Explanation: 32 g of oxygen = 1 mole of O2For 8 frames, the number of moles is 8/32 = 0.25 moles of O21 mole of O2 equals 1 mole of CO2Then, 0.25 moles of O2 equal 0.25 moles of CO2

Q125. London dispersion forces are the only forces present among?

• A. Atoms of helium in gaseous state at high temperature✓
• B. Molecules of water
• C. Molecules of NH3
• D. Molecules of HCl gas

Explanation: Option A is correct because helium atoms are non-polar and only exhibit London dispersion forces. These forces arise due to temporary fluctuations in the electron cloud, making them the sole intermolecular force present in helium gas. Option B is incorrect because water molecules exhibit hydrogen bonding, a much stronger force than London dispersion forces. Option C is incorrect because ammonia molecules also exhibit hydrogen bonding. Option D is incorrect because, in addition to London dispersion forces, HCl molecules experience dipole-dipole interactions due to their polarity.

Q126. Electrical conductivity of graphite is greater in one direction than in another due to

• A. Isomorphism
• B. Cleavage plane
• C. Anisotropy✓
• D. Symmetry

Explanation: Anisotropy means having a physical property that has a different value when measured in different directions Graphite is a crystalline, anisotropic solid. Graphite can conduct electricity parallel to the planes of a hexagon but its insulator conducts electricity in a direction that is perpendicular to the planes.

Q127. Number of neutrons in 6630Zn is:

• A. 30
• B. 35
• C. 38
• D. 36✓

Explanation: Number of neutrons = Mass number - atomic number Number of neutrons = 66 - 30 Number of neutrons = 36

Q128. The maximum number of electrons in an electronic configuration can be calculated by using formula:

• A. 2 (2l + 1)
• B. 2n2 + 2
• C. 2n2✓
• D. 2n2 + 1

Explanation: ( 2n^2) n=number of shells A.2(2l+1) is the formula for the number of electrons in a subshell.

Q129. Calculate the number of bonds and bonds in the molecule:

• A. 1π and 5σ bonds✓
• B. 2π and 4σ bonds
• C. 3π and 3σ bonds
• D. 6π and 6σ bonds

Explanation: The given structure is ethene; we know ethene forms a double bond. Carbon can form four bonds in ethene; each carbon forms three sigma bonds, two with hydrogen and one with the other carbon, and it forms one pie bond with the other carbon. So there will be a total of 5 sigmas and 1 pie bond.

Q130. ½ H2(g) → H(g) ΔH = 218 kJmol-1 In this reaction, ΔH will be called:

• A. Enthalpy of atomization✓
• B. Enthalpy of decomposition
• C. Enthalpy of formation
• D. The enthalpy of the dissociation

Explanation: The standard enthalpy of atomization of an element is deined as the amount of heat absorbed when one mole of gaseous atoms are formed from the element under standard conditions. Here H2 molecule is converted into H-atoms so enthalpy in this case is enthalpy of atomization.

Q131. Mg + 1/2 O2(g) → MgO(g) H=-692 kJmol-1 at STP. The enthalpy of the above reaction will be called:

• A. ΔH°at
• B. ΔH°s
• C. ΔH°sol
• D. ΔH°f✓

Explanation: The standard enthalpy of formation of a compound is the amount of heat absorbed or evolved when one mole of the compound is formed from its elements. It is denoted by ΔH°f . Here, 1 mole of MgO is forming from its constituent elements (Mg and O) so enthalpy here is the enthalpy of formation, which is defined as the change in enthalpy when one mole of a compound is formed from its respective elements in standard state.

Q132. Freezing point will also be defined as that temperature at which its solid and liquid phases have the same

• A. Concentration
• B. Ratio between the particles
• C. Vapour pressure✓
• D. Attraction between the phases

Explanation: It's the standard definition of a Freezing point. The freezing point is "the temperature at which the vapor pressure of the substance in its liquid phase is equal to its vapor pressure in the solid phase," which means that at that temperature the same amount of atoms or molecules are bonding or breaking between solid and liquid at the same rate

Q133. What mass of NaOH is present in 0.5 mol of sodium hydroxide?

• A. 40 g
• B. 2.5 g
• C. 5 g
• D. 20 g✓

Explanation: Sodium hydroxide = NaOH Molar mass of NaOH = 39.99 We know that number of moles = mass/molar mass 0.5 = mass/39.99 Mass =19.99 19.99 g can be written as 20 g.

Q134. The diagram shows a galvanic cell. The current will flow from:

• A. Hydrogen electrode to copper electrode✓
• B. Copper electrode to hydrogen electrode
• C. Hydrogen electrode to HCl solution
• D. CuSO4 solution to hydrogen electrode

Explanation: The reduction potential of copper is greater than that of hydrogen so in that case, the copper electrode will act as a cathode and S.H.E will act as an anode so electrons will flow from S.H.E to the copper electrode Key point: S.H.E. acts as a cathode (gets reduced) when attached to an electrode of metal except for Cu, Ag,AU, and Pt.

Q135. Study the following redox reaction and answer the following question:10Clˉ +16H+ + 2MnO4ˉ → 5Cl2 + 2Mn2+ + 8H2O

• A. Manganese is oxidized from +7 to +2
• B. Chlorine ions are reduced from -1 to zero
• C. Chlorine is reduced from 0 to -1
• D. Manganese is reduced from +7 to +2✓

Explanation: The correct change in oxidation numbers

Q136. Human blood maintains its pH between:

• A. 6.50–7.00
• B. 7.20 - 7.25
• C. 7.50 - 7.55
• D. 7.35–7.40✓

Explanation: Knowledge-based question Human blood acts as a buffer and it can maintain a pH between 7.3 and 7.4

Q137. Value of Kspfor PbSO4 systems at 25 °C is equal to:

• A. 1.6 x 10-5 mol2dm-6
• B. 1.6 x 10-6 mol2dm-6
• C. 1.6 x 10-8mol2dm-6✓
• D. 1.6 x 10-7 mol2dm-6

Explanation: The question is knowledge-based and it can be solved that way (from Punjab textbook page no243) The solubility of PbSO4 at 25 degrees is 0.038 ​PbSO^-4 ⇌Pb^+2+SO4^2− ​s=mass/molar mass So S =1.254×10^−4 Here, we need s^2 So S^2 =1.573×10^-8

Q138. 2A + B → Product If the reactant ‘B’ is in excess, the order of reaction with respect to ‘A’ in given rate law is: Rate = k[A]2[B] is:

• A. 2nd order reaction✓
• B. 1st order reaction
• C. Pseudo 1st order reaction
• D. 3rd order reaction

Explanation: Rate equation is mentioned and in case rate equation, especially order of reaction, is mentioned, then those are the only things to be considered. In this case, oder of reaction is 2+0=2 (SECOND ORDER).

Q139. The rate constant ‘k’ is 0.693 min-1. The half-life for the first-order reaction will be:

• A. 1 min✓
• B. 2 min
• C. 0.693 min
• D. 4 min

Explanation: For first order reactions, half life is constant, which means that half life is independent of initial concentration. For the first order reactions: t1/2 = 0.693/k t1/2 = 0.693/0.693 t1/2 = 1min

Q140. Melting points of Group II-A elements are higher than those of Group I-A because:

• A. Atoms of II-A elements have smaller size
• B. II-A elements are more reactive
• C. Atoms of II-A elements provide two binding electrons✓
• D. I-A elements have smaller atomic radius

Explanation: Metallic character as well as melting and boiling increase until period number three because the number of free electrons available for forming a metallic bond increases, so strong metallic bonds are formed As a result, melting Melting/Boiling boiling increases. Group-IIA offers two electrons for bonding while Group-IA offers one electron for bonding so it means IIA forms a stronger metallic bond.

Q141. The ionic radius of the fluoride ion is:

• A. 72 pm
• B. 95 pm
• C. 136 pm✓
• D. 157 pm

Explanation: The atomic radius of fluorine is 72pm, but when an electron is added, the affective nuclear charge decreases so the ionic radius of an anion is always greater than the atomic radius for fluoride, it is 136pm. Key point: fluoride is the anion of fluorine.

Q142. 2NaOH(aq) + Cl2(g) → NaCl + NaClO + H2O proceed at:

• A. 500 °C
• B. 200 °C
• C. -10 °C
• D. 15°C✓

Explanation: Reactant is present in aqua state (liquid) for the given options it is only possible at 15 degrees

Q143. Which halogen molecule, "X2," has the lowest dissociation energy?

• A. Cl2
• B. Br2
• C. I2✓
• D. F2

Explanation: The correct answer is I2. Among the halogen molecules, iodine (I2) has the weakest bond due to its large atomic size, which leads to poorer orbital overlap and therefore the lowest bond dissociation energy. Although F2 has a small atomic size, it experiences electron-electron repulsion that weakens its bond; however, it is still stronger than I2. Cl2 and Br2 have relatively stronger bonds than I2 due to better orbital overlap, resulting in higher dissociation energies.

Q144. The anomalous electronic configuration shown by chromium and copper among the 3-D series of elements is due to:

• A. Color of ions of these metals
• B. Variable oxidation states of metals
• C. Stability associated with this configuration✓
• D. Complex formation tendency of metals

Explanation: Two types of electronic configurations are the most stable 1-Completely filled 2: Completely and Partially filled Example: for P subshell 6, having 3 electrons, the p subshell is the most stable The same is the case for the D orbital, in which 10 and then having 5 electrons in the D subshell is the most stable Cr, by having 5 electrons in the D subshell (completely partially filled), is more stable than having 4 electrons in the D subshell, so Cr shows anomalous behavior by having an incomplete 4s subshell. Cu can give a more stable electronic configuration by having 10 electrons in the sub subshell (completely filled) instead of 9 electrons in the D subshell.

Q145. Which element of 3d series of periodic table shows the electronic configuration of 3d8, 4s2?

• A. Copper
• B. Cobalt
• C. Zinc
• D. Ni✓

Explanation: For remembering 3D series, we have a mnemonic

Q146. The percentage of nitrogen in ammonium nitrate is:

• A. 46%
• B. 82%
• C. 35%✓
• D. 13%

Explanation: An explanation is given below:

Q147. Which one of the following is an anhydride of sulfuric acid?

• A. Sulphur (III) oxide✓
• B. Sulphur dioxide
• C. Iron pyrite
• D. Disulphur dichloride

Explanation: An anhydride is a compound that, when combined with water, forms an acid or base.When SO₂ reacts with water, it forms sulfurous acid (H₂SO₃):SO₃ + H₂O --> H₂SO₄

Q148. During the contact process of H2SO4 synthesis, the following reaction occurs:2SO2(g) + O2(g) ⇌ 2SO3(g) H = -96 kJmol-1Which step is used to increase the yield of SO3?

• A. The temperature is raised to very high degree
• B. SO3 formed is removed very quickly✓
• C. Both temperatures and pressure are kept very low
• D. An excess of air is used to drive the equilibrium to the right side

Explanation: In this case, the yield of the product can be increased by decreasing temperature, increasing pressure, and continuously removing the product.

Q149. The synthesis of ammonia by Haber’s process is a reversible reaction. What should be done to increase the yield of ammonia in the following reaction?N2(g) + 3H2(g) ⇌ 2NH3(g) H = -92 kJmol-1

• A. Pressure should be decreased
• B. Ammonia should remain in reaction mixture
• C. Pressure should be increased✓
• D. The concentrationConcentration of nitrogen should be decreased

Explanation: Enthalpy is -ve, which means exothermic reaction and is favored at low temperatures. The number of moles is lower on the product side, meaning the reaction is favored by high pressure. In this case, the product will increase because pressure is increased, which means the reaction will go in direction of lesser number of moles.

Q150. Which one of the following reactions shows the combustion of a saturated hydrocarbon?

• A. C2H4 + 3O2 → 2CO2 + 2H2O
• B. CH4 + 2O2 → CO2 + 2H2O✓
• C. CH4 + 12 O2 = CH3OH (conditions: (Conditions:Cu, 400°C, 200 atm)
• D. C2H2 + 5/2 O2 → 2CO2 + H2O

Explanation: Key points here: The products of combustion are always H2O and C02 2-saturated means those having in which carbon form only single bonds

Q151. Skeletal formula of a hydrocarbon is given below. What is the IUPAC name of the compound?

• A. 3, 3-dimethyl-3-hexene
• B. 3, 4-dimethyl-3-hexene✓
• C. 3-hexene
• D. 2,3-dimethyl-1-hexene

Explanation: KEY POINTS the structure is a six-carbon Hydrocarbon containing two methyl substitutions and a double bond Metal substitution are present at carbon numbers 3 and 4 A double bond is present at carbon number 3

Q152. Which one of the following pairs can be cis-trans isomer of to each other?

• A. CHCl=CCl2 and CH2=CH
• B. CHCl=CH2 and CH2=CHCl
• C. CH3CH=CHCH3 and H3CCH=CHCH3✓
• D. CH3CH3 and CH2=CH

Explanation: For geometric isomers, the basic conditions are Alternative groups are present in our carbons atoms There should be a carbon-carbon double bond

Q153. The mechanism followed by the reaction below is:CH3CH2Br → H2C=CH2 + HBr (Conditions: alcoholic KOH)

• A. E2✓
• B. E1
• C. SN1
• D. SN2

Explanation: The formation of ethene shows that the reaction is elimination reaction Primary alkyl halides follow the E2 mechanism The alcohol medium shows elimination reaction.

Q154. The average bond energy of C-Br is

• A. 228 kJmol-1
• B. 200 kJmol-1
• C. 250 kJmol-1
• D. 290 kJmol-1✓

Explanation: Knowledge-based questions have to be remembered orally >solution: C-C bond energy is 346kcal for each carbon, or 173 kJ/mol Br-br bong energy is 194kcal for each carbon; it is 96.3 kJ/mol For C-Br bond energy, 173+96.3 =270kj/mol The nearest value to 270 is 290.

Q155. Which one of the following is not a nucleophile?

• A. NH2ˉ
• B. H2O
• C. BF3✓
• D. CH3ˉ

Explanation: Nucleophiles are electron donors and they usually have a negative charge.

Q156. Which one of the following is an appropriate indication of positive iodoform test?

• A. Formation of H2O
• B. Release of H2 gas
• C. Brick red precipitate
• D. Yellow crystal✓

Explanation: The formation of yellow crystals is an appropriate indication of a positive iodoform test. When a compound containing a methyl ketone or secondary alcohol group undergoes the iodoform test, it reacts with iodine and a base to form iodoform (CHI3) as a yellow precipitate. This yellow precipitate is often observed in the form of yellow crystals, indicating a positive result for the presence of the functional groups targeted by the iodoform test.

Q157. Which one of the following is the proper classification of the following is the proper classification of formula given below?

• A. Primary
• B. Secondary
• C. Tertiary✓
• D. Polyhydride

Explanation: It is a tertiary alcohol. We can recognize the tertiary alcohol by seeing whether the C atom attached to the OH group (also known as alpha Carbon) is directly attached to three C atoms or not. In the given figure, it is clear that the given alcohol is tertiary

Q158. Which one of the following is an appropriate structure for the product of bromination?

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

Explanation: We are asked to describe the possible product of bromination. From the question, we can possibly conclude that the OH group is already present on the benzene ring, or, in other words, we are considering phenol. So we have to tell you the possible product of the bromination of “phenol”. As OH is an orthopedic directing group, So the option having product that has Br on Ortho and Para positions is the right one, which in this case is option C

Q159. Which one of the following is an appropriate name for the compound given below?

• A. 1,3,6-Trinitrophenol
• B. m-Nitrophenol
• C. Tartaric acid
• D. Picric acid✓

Explanation: Picric acid, also called 2,4,6-trinitrophenol, is a pale yellow, odorless, crystalline solid that has been used as a military explosive, as a yellow dye, and as an antiseptic. There are two functional groups in picric acids: OH and NO2. According to the priority list of Functional groups -COOH> -COOR> -CHO> -CO> -OH> -NH2 > Alkene/ Alkynes OH should be given priority, i.e., position 1, and then nitro groups are named accordingly. As OH is prioritized, we can use the name phenol as well. In this way, Nitro groups are given positions 2, 4, and 6, as illustrated below

Q160. It is the general formula of:

• A. 2, 4-Dinitrophenyl hydrazine✓
• B. 1, 3-Dinitrophenyl hydrazone
• C. Phenyl hydrazone
• D. 2, 4-Dinitrophenyl hydrazone

Explanation: Hydrazone consists of a carbon-nitrogen double bond, i.e., R1R2C=NNH2. In Phenyl hydrazone, one H atom of hydrazone is replaced by a phenyl ring. Now if we attach two nitro groups at positions 2 and 4, as given in the question, the product we have is 2,4-nitrophenyl hydrazine.

Q161. Which one of the following is the IUPAC name of the structure given below?

• A. Propionaldehyde
• B. Methanone
• C. Acetaldehyde
• D. Methanal✓

Explanation: Methanal/formaldehyde is a naturally occurring organic compound with the formula CH₂O and structure H−CHO.

Q162. Which one of the following tests is given by both aldehydes and ketones?

• A. Silver mirror test
• B. Fehling’s solution
• C. 2, 4 DNPH test✓
• D. Benedict’s solution test

Explanation: Only aldehydes can react with mild reagents such as Fehling’s solution and Benedict's solution and also show positive results with the silver mirror test, whereas 2,4-DNPH reacts with carbonyl compounds (both aldehydes and ketones) to give a colored precipitate.

Q163. CH3COOH + CH3CH2OH ⇌ CH3COOC2H5 + H2O Which one of the following will act as a catalyst in the above reaction?

• A. HNO3
• B. H2SO4✓
• C. Acidified potassium dichromate
• D. SOCl2

Explanation: In this reaction, Ester is being formed. Esters are produced when carboxylic acids are heated with alcohols in the presence of an acid catalyst. The catalyst is usually concentrated sulfuric acid. Dry hydrogen chloride gas is used in some cases, but these tend to involve aromatic esters.

Q164. CH3COOH + PCl5 → ?

• A. POCl2, CH3COCl2 and HCl
• B. POCl3 + CH3COCl2 + H2
• C. CH3COCl, POCl2 and HCl
• D. POCl3, CH3COCl and HCl✓

Explanation: In the given reaction, the acetic acid reacts with PCl5 to form acetyl chloride as a major product, with the production of POCl3 and HCl.

Q165. Which one of the following reaction of carboxylic acid is reversible?

• A. Esterification✓
• B. Reaction with PCI5
• C. Salt formation
• D. Reaction with SOCl2

Explanation: Among the options given, the only reversible reaction involving carboxylic acids is A) Esterification, where carboxylic acids and alcohols can interconvert to form esters and water.The other reactions involve the conversion of carboxylic acids into different compounds but do not necessarily revert back to the original carboxylic acid. Esterification is a reversible reaction involving a carboxylic acid and an alcohol, often in the presence of an acid catalyst.In this reaction, an ester and water are formed.The general reaction equation for esterification is: Carboxylic Acid + Alcohol ⇌ Ester + WaterThe reaction can proceed in both directions, forming ester from carboxylic acid and alcohol, as well as converting ester back to carboxylic acid and alcohol under suitable conditions.The equilibrium between reactants and products is established, making esterification a reversible process.

Q166. Select the best option, indicating the name of the structure given below

• A. Cation
• B. Neutral Amino Acid
• C. Internal Salt✓
• D. Anion

Explanation: There is an internal transfer of a hydrogen ion from the COOH group to the NH2 group, leaving an ion with both a negative charge and a positive charge. This is called a zwitterion, or internal salt. The term internal salt refers to the dipolar character of amino acids.

Q167. When acid is added to an amino acid, which one of the following will act as a base?

• A. NH3+
• B. COO_✓
• C. H+
• D. R group

Explanation: If you decrease the pH by adding an acid to a solution of an amino acid, the -COO- part of the zwitter ion picks up a hydrogen ion, thereby acting as a base.

Q168. Which of the following graphs represents the output of an X-ray?

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

Explanation: The given graph in option A represents the observed intensity of the X-rays emitted by an X-ray tube as a function of wavelength. The sharp peaks denote characteristic X-ray spectra. At other wavelengths, the intensity varies gradually, so that no definite line of separation can be drawn between any two of them. These X-rays are called continuous X-rays.

Q169. The continuous spectrum of X-rays is formed due to:

• A. Characteristics of X-rays
• B. Bremsstrahlung X-ray✓
• C. Soft X-ray
• D. Hard X-ray

Explanation: Continuous X-rays are created when free-moving electrons electromagnetically interact with nuclei. These are also called Bremsstrahlung X-rays. Bremsstrahlung, from bremsen "to brake" and Strahlung "radiation" i.e., "braking radiation" or "deceleration radiation", is electromagnetic radiation produced by the deceleration of a charged particle when deflected by another charged particle, typically an electron by an atomic nucleus.

Q170. The wavelength of gamma rays is:

• A. Equal to the X-rays
• B. Longer to the X-rays
• C. Shorter than the X-rays✓
• D. border to the X-rays

Explanation: Gamma rays are electromagnetic radiation with the shortest wavelength and highest energy. X-rays are less energetic and thus have a longer wavelength.

Q171. Thorium is transformed after the transmission of a beta particle into:

• A. Bismuth
• B. Protactinium✓
• C. Polonium
• D. Palladium

Explanation: Thorium-234 has a half-life of 24.1 days, emitting a beta particle that results in its transformation to protactinium-234. In this way, the decay equation is obeyed. In beta decay, the mass number remains the same, but the atomic number is increased by 1. In the case of Thorium, after beta decay, a sepia with Atomic number 91 and mass number 234 should be formed.

Q172. Emission of -rays from radioactive elements results in:

• A. Bismuth
• B. Protactinium
• C. Polonium✓
• D. Palladium

Explanation: The emission of gamma rays, or γ-rays, from radioactive elements is a process that typically occurs when an unstable nucleus undergoes radioactive decay. Gamma rays are high-energy electromagnetic radiation that does not alter the atomic number or mass number of the element; thus, the element does not change into another element. Polonium is known to emit gamma rays as part of its decay process. On the other hand, Bismuth, Protactinium, and Palladium are not commonly associated with gamma ray emission due to their typical decay modes or stable nature.

Q173. The relation between the decay constant ‘λ’ and the half-life T12 of a radioactive substance is:

• A. λ = 1/T1/2
• B. λ = 0693 T1/2
• C. λ = T1/2
• D. λ = 0.693/T1/2✓

Explanation: The time required for half of the original population of radioactive atoms to decay is called the half-life. The relationship between the half-life, T1/2, and the decay constant is given by T1/2 = 0.693/.

Q174. Radioisotopes that are used to combat cancer of the thyroid gland are:

• A. Iodine-131✓
• B. Phosphorous-32
• C. Strontium-90
• D. Cobalt-60

Explanation: Radioiodine, 131I, has been used for the treatment of hyperthyroidism and metastases of well-differentiated thyroid carcinoma.

Q175. Sodium-24 is used for:

• A. Sterilization
• B. Study of circulation of blood✓
• C. Skin Cancer
• D. Thyroid Cancer

Explanation: Na-24 is a radioisotope that is used to study the circulation of blood.

Q176. Energy radiation absorbed at the rate of one joule per kilogram is called:

• A. 1 Rad
• B. 1 Sievert
• C. 1 Yellow
• D. 1 Gray✓

Explanation: 1 Gray is the unit of absorbed radiation equal to the dose of one joule of energy absorbed per kilogram of matter, or 100 rad. The unit is named for the British physician L. Harold Gray (1905–1965), an authority on the use of radiation in the treatment of cancer.

Q177. The time period ‘T’ of a simple pendulum depends on its length ‘l’ and acceleration due to gravity ‘g’ using unit dimensions. The correct equation for the time period is:

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

Explanation: T=2πgl The period of a simple pendulum is given by T = 2 gl, where l is the length of the pendulum and g is the acceleration due to gravity. The time period is directly proportional to length and inversely proportional to gravity.

Q178. The unit for electric charge is the coulomb, and one Coulomb in terms of the base unit is equivalent to:

• A. Am
• B. Js-1
• C. As✓
• D. C

Explanation: In terms of SI base units, 1 C is the equivalent of 1 ampere-second, which can be expressed as 1 C = 1 A ⋅ 1 s (or C = A ⋅ s). This can also be thought of as an ampere being equal to 1 coulomb divided by 1 s, as in 1 A = 1 C / 1 s (or A = C / s). In other words, if the current in a circuit is 1 A, 1 C of charge passes through a point in the circuit every second

Q179. A man in an elevator ascending with acceleration will conclude that his weight is:

• A. Increased✓
• B. Decreased
• C. Reduced to zero
• D. Remain Constant

Explanation: As the elevator pushes upward, the downward force, i.e., weight, will appear to increase. Weff = mgeff geff = (g + a)

Q180. If we double the moment arm, the value of torque becomes:

• A. Half
• B. Three-times
• C. Two-times✓
• D. Four-times

Explanation: A moment arm is basically defined as the length between a joint axis and the line of force acting on that joint. Torque=Force×Moment Arm τ=r×F Hence, when the moment arm is doubled, the torque is also doubled

Q181. When fluid is incompressible, the quantity is constant.

• A. Mass
• B. Density✓
• C. Pressure
• D. Force

Explanation: In an incompressible fluid, particles have a constant density. An incompressible fluid is defined as one whose density does not change on applying pressure; it's an ideal liquid and does not exist in real life.

Q182. The minimum distance from the eye at which an object appears to be distant is:

• A. 25 cm✓
• B. 22 cm
• C. 35 cm
• D. 20 cm

Explanation: This is approximately 25 cm from the eye. The normal human eye can focus a sharp image of an object on the eye if it is located anywhere between infinity and a point known as the near Point.

Q183. Using the relation for the magnifying power Lo, M = 1 + d/f, if f = 5 cm and d = 25 cm, then M will be:

• A. 5
• B. 7
• C. 6✓
• D. 8

Explanation: Using M= 1 + d/f Putting values given in the question M= 1+25/5 M= 1+5=6

Q184. Resonance occurs when the driving frequency is:

• A. Greater than natural frequency
• B. Unequal the natural frequency
• C. Less than natural frequency
• D. Equal to the natural frequency✓

Explanation: Resonance occurs when the driving frequency equals the natural frequency. Resonance occurs when an object experiences an oscillating force that's close to one of its “natural” frequencies, at which it easily oscillates.

Q185. The red shift measurement of Doppler effect of galaxies indicate that the universe is:

• A. Expanding✓
• B. Contracting
• C. Stationary
• D. Oscillating

Explanation: The Doppler red-shift of light observed from distant stars and galaxies gives evidence that the universe is expanding (moving away from a central point)

Q186. The audible frequency range for human hearing lies in the range:

• A. 2-2000 kHz
• B. 15-50000 kHz
• C. 20-20000 Hz✓
• D. 20-20000 kHz

Explanation: Hearing range describes the range of frequencies that can be heard by humans or other animals, though it can also refer to the range of levels. The human range is commonly given as 20 to 20,000 Hz, although there is considerable variation between individuals, especially at high frequencies, and a gradual loss of sensitivity to higher frequencies with age is considered normal. Information from the course textbook

Q187. Tuning a radio is the best example of:

• A. Natural resonance
• B. Mechanical resonance
• C. Free resonance
• D. Electrical resonance✓

Explanation: Tuning a radio is the best example of electrical resonance. When we turn the knob of a radio to tune a station, we are changing the natural frequency of the electric circuit of the receiver to make it equal to the transmission frequency of the radio station. When the two frequencies match, energy absorption is at its maximum, and this is the only station we hear.

Q188. The ratio of applied stress to volumetric strain is called:

• A. Bulk Modulus✓
• B. Shear Modulus
• C. Tensile modulus
• D. Young’s Modulus

Explanation: Within the elastic limit, the ratio of volumetric stress to the corresponding volumetric strain in a body is always constant, which is called the bulk modulus of elasticity. In simpler words, the bulk modulus is nothing but a numerical constant that is used to measure and describe the elastic properties of a solid or fluid when pressure is applied to all the surfaces.

Q189. The wire made of copper belongs to which specific kind of material?

• A. Ductile material✓
• B. Tough material
• C. Brittle material
• D. Deformed material

Explanation: Ductility is the ability of a material to be drawn or plastically deformed without fracture. It is therefore an indication of how 'soft' or malleable the material is.Hence, Copper is a versatile material as it can be drawn into sheets.

Q190. The relation R/NA = 1.38 x 10-25 JK-1 in a gas law is known as:

• A. Avogadro’s constant
• B. Charles constant
• C. Newton’s constant
• D. Boltzmann’s constant✓

Explanation: The relation R/NA = 1.38 x 10-25 JK-1 in a gas law is known as the Boltzmann constant. It is a physical constant that provides the computation of the amount of energy due to the random thermal motions of the particles making up the substance.

Q191. The relation ‘PV = nRT’ shows which law of physics:

• A. Charles Law
• B. Avogadro’s Law
• C. Newton’s Constant
• D. Ideal Gas Law✓

Explanation: The ideal gas law, also called the general gas equation, is the equation of state of a hypothetical ideal gas. It shows the relation between the pressure P, volume V, and temperature T of gas in the limit of low pressures and high temperatures, such that the molecules of the gas move almost independently of each other. In such a case, all gases obey an equation of state known as the ideal gas law: PV = nRT, where n is the number of moles of the gas and R is the universal (or perfect) gas constant.

Q192. The rapid escape of air from a burst tire is an example of

• A. Adiabatic processes✓
• B. Isothermal process
• C. Cooling process
• D. First law of thermodynamics

Explanation: The burst of a tire is a sudden process. The process occurs instantaneously, such that the system does not get sufficient time to exchange heat with the surroundings; therefore, Q = 0. And we know that in diabetics, heat is neither absorbed nor released by a system, i.e., Q = 0. Hence, the bursting of a tire is an example of an adiabatic process.

Q193. Which relation exactly describes the isothermal process?

• A. Q = W✓
• B. W = -U
• C. Q = -ΔU
• D. Q = ΔU + W

Explanation: An isothermal process is a thermodynamic process in which the temperature of a system remains constant. The transfer of heat into or out of the system happens so slowly that thermal equilibrium is maintained. In an isothermal process, T = 0. If T = 0, then we can say that U = 0. According to the 1st law of thermodynamics, Q = U+W. In this case, the first law can be written as Q=W

Q194. If a turbine is working as a heat engine and takes heat from a hot body (427 °C) and exhausts it into a body at 77 °C, then what is the possible efficiency?

• A. 50%✓
• B. 70%
• C. 90%
• D. 95%

Explanation: The efficiency of a Carnot engine is entirely a function of the temperatures of the hot and cold reservoirs you use. It can be calculated using this equation.

Q195. Which one of the following is the Boolean expression of the NAND gate?

• A. X = A.B
• B. B X = A + B
• C. X = Ā.B̄✓
• D. X = Ā + B̄

Explanation: The Boolean expression given for a NAND gate is that of logical addition and it is opposite to the AND gate The Boolean algebra for AND gate is X=A.B So, the Boolean algebra for the NAND gate is: X=A.B

Q196. Which one of the following is the truth table of the NAND gate?

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

Explanation: The NAND gate, or “NotAND” gate, is the combination of two basic logic gates, the AND gate, and the NOT gate, connected in series. The output of a NAND gate is high when either of the inputs is high or if both inputs are low. In other words, the output is always high and goes low only when both inputs are high. The logic NAND function is given by the Boolean expression X=A.B. The truth table of a NAND gate is given below

Q197. If the length, width, and separation between the plates of a parallel plate capacitor are doubled, then its capacitance becomes:

• A. Double✓
• B. Half
• C. Four-times
• D. Eight-times

Explanation: The capacitance of a parallel plate capacitor is given by C = A/D Where ε is the permittivity of the dielectric, A is the area of the plates, and D is the distance between them. As D is in the denominator, capacitance is inversely proportional to the distance between plates, or separation. As A is in the numerator, it is directly proportional to C, where A = width x length. It then follows that if the length, width, and separation between the plates of a parallel plate capacitor are doubled, then its capacitance will also double.

Q198. The resistance between two opposite faces of a square thin film of area 1 mm2 having a thickness of 1 m if the resistivity of the material is 10-6 Ω will be:

• A. 1000 Ω
• B. 100 Ω
• C. 1 Ω✓
• D. 10 Ω

Explanation: Given data Area, A= 1mm2 Resistivity, ρ= 10-6Ωm Thickness, x= 10-6m Now we have Resistance, R=ρl/A where A= = length (l) x thickness (x) Thus, R= ρll.x Or R= ρ/x Substituting the values , R= 10-6Ωm10-6m R= 1Ω

Q199. Total resistance between ‘A’ and ‘B’ in the given circuit is:

• A. 5.6 Ω
• B. 3.33 Ω
• C. 0.33 Ω
• D. 6.6 Ω✓

Explanation: The total resistance can be found by using the method of successive reduction, as shown below

Q200. ‘F’ is the maximum force acting on a conductor. Now if we change the direction of the conductor by making an angle of 45° with the magnetic field, then the force becomes:

• A. F/2
• B. 2F
• C. F/√2✓
• D. √2 F

Explanation: As we know, the force experienced by the current-carrying conductor is given by F'=IBLsinθ If θ= 45o F'=Fsin45° F'=F(0.707) F'=F/√2

Q201. If we double all the parameters of the force acting on the current-carrying conductor and θ = 90°, then the magnetic force becomes:

• A. Half
• B. Double
• C. Eight-times✓
• D. Four-times

Explanation: As we know, the force experienced by the current-carrying conductor is given by F=IBL (sinθ=1) F'=IBLsinθ If = 90o If all other parameters, i.e. I, B, and L, are doubled, then we can write F'=2Ix2Bx2Lsin90 F’= 8IBL F’=8F

Q202. The force acting on the current-carrying conductor will be maximum if the angle between the magnetic field and conductor is:

• A. 0°
• B. 30°
• C. 90°✓
• D. 60°

Explanation: The maximum force on a current-carrying conductor occurs when the current direction and the magnetic field's direction are perpendicular to one another (i.e., a 90-degree angle between directions). F=iBlsinθ. This is the maximum when sin=1 or θ=/2 or 90 degrees.

Q203. The shadow of the bones in X-ray photographic film appears lighter than the surrounding flesh due to:

• A. Bones reflect greater number of X-rays
• B. Bones absorb a lower amount of X-rays
• C. Bones absorb greater number of X-rays✓
• D. Bones totally reflect X-rays

Explanation: X-rays are a technique used in radiography in which electromagnetic radiation differentially penetrates tissues inside the body and creates images of these structures on photographic film. The greater the density of the material that the X-rays pass through, the more rays are absorbed. Dense bone absorbs much of the radiation, while soft tissue (muscle, fat, and organs) allows more of the X-rays to pass through them. As a result, bones appear white on the X-ray, soft tissue shows up in shades of gray, and air appears black.

Q204. The atom is excited to an energy level Ei from its ground-state energy level Eo, the wavelength of the radiation emitted is:

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

Explanation: The atom is excited to an energy level Ei from its ground state energy level Eo, the wavelength of the radiation emitted is given as follows: Using Planck’s equation E=hf E=hc/λ ΔE= hc/λ λ = hc/ ΔE ΔE = Ei – Eo λ = hc/ Ei – Eo

Q205. Which one of the following gases is the lasing or active medium in the laser tube?

• A. Hydrogen
• B. Helium✓
• C. Neon
• D. Carbon dioxide

Explanation: A gas laser is a laser in which an electric current is discharged through a gas inside the laser medium to produce laser light. In gas lasers, the laser medium is in a gaseous state. Gas lasers are used in applications that require laser light with very high beam quality and long coherence lengths. In gas lasers, the laser medium, or gain medium, is made up of a mixture of gases. This mixture is packed into a glass tube. The glass tube filled with a mixture of gases acts as an active medium or laser medium. The gas mixture is mostly helium, so helium atoms can be excited. The excited helium atoms collide with neon atoms, exciting some of them to a state that radiates 632.8 nm. Without helium, the neon atoms would be excited mostly to lower excited states, responsible for non-laser lines.

Q206. The target of an X-ray tube is made up of which metal?

• A. Iron
• B. Nickel
• C. Brass
• D. Tungsten✓

Explanation: Most x-ray tube anodes are made of tungsten (the target material). Tungsten has a high atomic number (Z = 74) and a high melting point of 3370 °C, with a correspondingly low rate of evaporation.

Q207. The X-rays consist of:

• A. high-energy proton
• B. High-energy electrons
• C. High-energy -rays
• D. High-energy photons✓

Explanation: X-rays are a form of electromagnetic radiation similar to visible light. Unlike light, however, x-rays have higher energy and can pass through most objects, including the body. Medical x-rays are used to generate images of tissues and structures inside the body. Hence, X-rays consist of photons, not particles.

Q208. In Bernoulli’s equation, the term 1/2 v2 is called:

• A. K.E. per unit volume✓
• B. K.E.
• C. K.E. per unit area
• D. K.E. per unit length

Explanation: Bernoulli’s equation formula is a relation between the pressure, kinetic energy, and gravitational potential energy of a fluid in a container. The formula for Bernoulli’s principle is given as follows: p+1/2ρv2+ρgh=constant Where p is the pressure exerted by the fluid, v is the velocity of the fluid, ρ is the density of the fluid, and h is the height of the container. Here 1/2 v2 represents K.E. per unit volume.

Q209. Potential energy per unit volume is given by

• A. mgh
• B. mgh/p
• C. gh
• D. pgh✓

Explanation: P.E/V = mgh/V = pgh

Q210. If the general equation for destructive interference is given by the relation Optic path difference = (m +12), where ‘m’ is an integer, then the first dark fringe that appears from ’m’ will be equal to:

• A. 23
• B. 12
• C. 0✓
• D. 1

Explanation: If general equation for destructive interference is given by the relation Optic path difference = (m+(1/2)), where 'm' is an integer, then first dark fringe that appears from 'm' will be equal to 0For destructive interference • m = 0 would give us the angle of the first-order dark fringe • m = 1 would give us the second-order fringe, etc. For both bright and dark fringes, the first-order fringe is the one closest to the central maximum.

Q211. For bright fringe formation, the path difference is:

• A. (n +½) λ where n = 0, 1, 2, ………….
• B. nλ where n = 0, 1, 2, ………….✓
• C. (2n + 1) λ/2 where n = 0, 1, 2, ………….
• D. ((n +1)/2) λ2 where n = 0, 1, 2, …………

Explanation: For maximum intensity or bright fringe to be formed at P Path difference, Δz = nλ (n = 0, ±1, ±2, . . . .)

Q212. Identify the mistake that needs to be corrected.Pasteur entered in the competition and settled the matter of spontaneous generation once and for all.

• A. Entered in✓
• B. Settled
• C. Once and for all
• D. No error.

Explanation: The sentence would have been grammatically correct if the verb ‘entered’ was not accompanied by it’s preposition ‘in’.The sentence "Pasteur entered in the competition and settled the matter of spontaneous generation once and for all" contains a minor grammatical error. It should be "Pasteur entered the competition" instead of "entered in the competition." Here's the corrected sentence:"Pasteur entered the competition and settled the matter of spontaneous generation once and for all."

Q213. Identify the error and choose the correct option:The first space traveller was dennis tito from united states.

• A. The first space traveller was Dennis Tito from the United States.✓
• B. The First Space Traveller was Dennis Tito, from, the United states.
• C. The first space traveller was Dennis Tito-from the United states.
• D. The first space traveller was Dennis Tito, from the United States.

Explanation: The spelling of traveller was wrong, and names are supposed to be written in Capitals.

Q214. Identify the mistake that needs to be corrected.Stevens was very delighted to see that he was declared more popular than any talk show just in the USA.

• A. Very
• B. To see that
• C. Than any✓
• D. The USA

Explanation: The trick to solving these types of questions is to read the question a few times in your head. It is not appropriate to compare a person with a non tangible thing such as a talk show. Also, it should be:“..than any OTHER talk show…” this sounds more grammatically accurate.

Q215. Identify the error and choose the correct option:The rehearsal session started and we have little time to spar for other activities.

• A. The rehearsal session started and we have little time to spare for other activities.✓
• B. The rehearsal session started, and we little time to spare for other activities.
• C. The rehearsal session starts and we has little time to spare for other activities.
• D. We are little time to spare for other activities, the rehearsals session starts.

Explanation: The intended word over here was ‘spare’ instead of ‘spar’. 'Spare' means to take out time for extra activities, while 'spar' means to destroy and finish something.

Q216. Spot the error in the following sentence. It should also help you to understand how can you make better use of the scientific method in your everyday living.

• A. To understand
• B. Can you✓
• C. Use of
• D. Living

Explanation: "can you": The phrase "can you" is grammatically incorrect in this sentence. It should be replaced with the word "to" to form a correct sentence. The corrected sentence would be: "how to." The underlined segment that contains the mistake is: "how can you make better use of the scientific method in your everyday living." The corrected sentence would be: "It should also help you understand how to make better use of the scientific method in your everyday life." Mistake: The phrase "can you" should be replaced with "to" to form a grammatically correct sentence.

Q217. Identify the mistake that needs to be corrected.Police in their investigation used coercive measure to get favourable statements from the accused.

• A. Their
• B. Used
• C. Measure✓
• D. From the accused

Explanation: The underlined segment that contains the mistake is "used coercive measure". The correct phrase should be "used coercive measures". The word "measure" is a singular noun, so it needs to be pluralized when it is used with the word "coercive."The correct sentence should read:Police in their investigation used coercive measures to get favorable statements from the accused.

Q218. Identity the word or phrase that needs to be changed for the sentence to be correct:He called me as a fool.

• A. Called
• B. Me
• C. As✓
• D. Fool

Explanation: The word ‘as’ over here is unnecessary, and the sentence will suffice without it.

Q219. Read carefully and choose the correct answer.

• A. Here is the paper clips you requested.
• B. Here's the paper clips you requested.
• C. Here are the paper clips you requested.✓
• D. Here are the box of paper clips you requested.

Explanation: Since paper clips is plural, are will be used as the helping verb.

Q220. Which one is correct? Read carefully.

• A. Flemings, born on the land, were becoming a medical family.
• B. The Flemings, born on the land, were becoming a medical family.✓
• C. Both are correct
• D. Both are wrong

Explanation: "The" is commonly used before family surnames to indicate them as a group. Option B correctly represents the idea of the sentence.