Fmdc 2018 — Solved Past Paper with Answers

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

• A. Critical
• B. Reluctant
• C. Happy
• D. Horrified✓

Explanation: Aghast means to be filled with horror or shock. Hence, the closest word to it would be horrified.

Q2. Select the word with the closest meaning to the given word: Ruminate

• A. Eat greedily
• B. Think carefully✓
• C. Work lazily
• D. Run fast

Explanation: Ruminate means to think deeply or carefully about something. Hence, B is the correct option.

Q3. Select the word with the closest meaning to the given word:Disruption

• A. Comfort
• B. Luxury
• C. Trouble✓
• D. Freedom
• E. Calm

Explanation: Disruption is a disturbance or problem which interrupts an event, process or activity. Therefore, C is the correct option.

Q4. Select the word with the closest meaning to the given word:Unambiguous

• A. Stagnant
• B. Hidden
• C. Clear✓
• D. muddy

Explanation: Unambiguous is something that is clear or precise. Hence, C is the correct answer.

Q5. Select the word with the closest meaning to the given word: Wrecked

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

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

Q6. Select the word with the closest meaning to the given word:Freight

• A. Worries
• B. Luggage✓
• C. Foolish
• D. Instruments

Explanation: Freight is the general term for goods transported from one place to another by any means. Hence, the correct answer is B.

Q7. Select the word with the closest meaning to the given word:Meditative

• A. Selfish
• B. Thoughtful✓
• C. Heedless
• D. Opinion

Explanation: Meditative means to be absorbed in mediation or considered thought. Hence, B is the correct answer.

Q8. Select the word with the closest meaning to the given word: Shabby

• A. Organised
• B. Untidy✓
• C. Reluctant
• D. Sensible

Explanation: Shabby means to be in poor condition through long use or lack of care. Therefore, the correct option would be B.

Q9. Select the word with the closest meaning to the given word: Forbid

• A. Prohibit✓
• B. Chide
• C. Permit
• D. Constraint

Explanation: Forbid means to refuse to allow something. Hence, the answer is A.

Q10. Select the word with the closest meaning to the given word: Prevent

• A. Stop✓
• B. Start
• C. Verify
• D. Confirm

Explanation: To prevent something means to keep (something) from happening. Therefore, the correct answer is A.

Q11. You should stick _ your promise. Choose the best option to fill in the blank.

• A. By
• B. To✓
• C. With
• D. In

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

Q12. Shah Jahan _ the great mosque in Delhi.

• A. Founded
• B. Raised
• C. Created✓
• D. Established

Explanation: "Created" will be used here as it is a synonym for built.

Q13. Nearly everyone dreams of building _ ideal house.

• A. Its
• B. Their✓
• C. Them
• D. His

Explanation: “Their” will be used here as it is used to show something belongs to or is associated with the people or things previously mentioned.

Q14. The injured player was taken _ the field.

• A. Off✓
• B. Of
• C. Out
• D. In

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

Q15. The box is _ green outside and white inside.

• A. Carved
• B. Created
• C. Painted✓
• D. Molded

Explanation: Since colors are referenced here, it means the correct option is “painted” as colors can only be painted onto things not carved or molded onto something.

Q16. Somebody has not turned the tap_.

• A. Of
• B. Off✓
• C. Over
• D. In
• E. Out

Explanation: The preposition "off" is used here as to turn off something. In this sense it means, to stop using a supply of water, gas, or electricity by turning a tap off, pressing a button, or moving a switch.

Q17. The doctor is going _ vaccinate me tomorrow.

• A. To✓
• B. On
• C. At
• D. With

Explanation: The expression, "going to", followed by a verb in the infinitive, allows us to express an idea in the near future as in this case the doctor is going to vaccinate me tomorrow.

Q18. I prefer fruits _ sweets.

• A. Then
• B. On
• C. Over✓
• D. From

Explanation: We use prefer to say we like one thing or activity more than another. Over is used when there are two clear choices in the phrase. Think of over as setting a list of preferences and putting one over top the other. I prefer jogging over running and walking or as in this case, I prefer fruits over sweets.

Q19. Ahmed _ me for a long time.

• A. Know
• B. Knows✓
• C. Known
• D. Knew

Explanation: “Knows” is used here as it is the present-tense form of the verb and is grammatically correct.

Q20. Did anyone do the work _?Fill in the blank.

• A. Themselves✓
• B. Himself
• C. Himselves
• D. None of the above

Explanation: They are all known as reflexive pronouns. Myself, yourself, himself, herself, itself are all singular - they refer to one person (or a 'thing' for itself). Ourselves, yourselves and themselves are all plural - they refer to more than one person, hence “Themselve” is used here as multiple people are being referred to in the question.

Q21. The diagram given below shows the stages of mitosis. What is the order of these stages during mitosis?

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

Explanation: 2= prophase 1= metaphase 4= anaphase 3= telophase Explanation: These phases are prophase, metaphase, anaphase, and telophase. These are the steps that take place in common cellular division. During anaphase, splitting of centromeres of chromosome takes place and hence separation of two chromatids of each chromosome occurs at anaphase and we can see the chromatids at two separate poles. During metaphase, all chromosome form a single plate. On the equatorial plate, chromosome appears two threaded. Prophase is a short phase and there is no pairing of homologous chromosome. We can see the degeneration of the chromatin material. During telophase, the two daughter cell start showing here and paves the way for cytokinesis.

Q22. Most bacteria require vitamins for which purpose?

• A. Source of energy
• B. Growth factors✓
• C. Source of carbon
• D. Source of electron donors

Explanation: Growth factors are organic compounds such as amino acids, purines, pyrimidines and vitamins that a cell must have for growth but cannot synthesizr itself. Typically a vitamin or a specific carbon source must be added to a growth medium in order to grow a specific organism.

Q23. Germ Theory of disease was proposed by:

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

Explanation: This is a fact. Robert Koch formulated the germ theory of disease.

Q24. Freeing of an object from all living organism, bacteria and their spores, fungi and their species is called:

• A. Sterilization✓
• B. Disinfection
• C. Decontamination
• D. Immunization

Explanation: Sterilization refers to the process in which all living cells, spores, and viruses are completely destroyed or removed from an object or environment. Once something is sterilized, it will remain sterile if properly sealed.

Q25. The process by which various components of cells including organelle can be isolated is called:

• A. Homogenization B
• B. Cell Fractionation✓
• C. Cell Fixation
• D. Gel Electrophoresis
• E. Ultracentrifuge

Explanation: Cell fractionation is a method to separate subcellular components, and isolate organelles and other subcellular components from one another.

Q26. Which of the following correctly shows structures which are found in a eukaryotic cell? (Yes present; No = absent)

• A. No No No
• B. No Yes No
• C. Yes No No
• D. Yes No Yes
• E. Yes Yes Yes✓

Explanation: Each eukaryotic cell has a plasma membrane, cytoplasm, a nucleus, ribosomes and mitochondria. The genetic material is present within the nucleus which is surrounded by nuclear membrane/nuclear envelope .

Q27. Which of the following term is used to describe the membrane of central vacuole?

• A. Tonoplast✓
• B. Myoplast
• C. Periplast
• D. Epi Tonoplast

Explanation: The tonoplast is the central vacuole's membrane in a plant cell. It is also known as the vacuolar membrane. It separates the contents of the central vacuole from the rest of the cell. It is made up of phospholipids and proteins, just like the cell membrane that covers the plant cell.

Q28. The major portion of (NH)2CO is excreted by:

• A. Sweat
• B. Saliva
• C. Urine✓
• D. Stool

Explanation: The major portion of (NH)2CO, also known as urea, is excreted by urine. However, urea is also excreted by sweat. It may be excreted through saliva. Stool contains negligible amount of urea.

Q29. In White Blood Cells, Monocytes have a short life period of_ hours.

• A. 10 - 20✓
• B. 21 - 30
• C. 31 - 35
• D. 36 - 40

Explanation: This is a fact. In White Blood Cells, Monocytes have a short life period of 10-20 hours. Some monocytes remain in the general blood circulation, but most of them enter body tissues. In tissues, monocytes develop into much larger phagocytic cells known as macrophages.

Q30. The fungal cell wall contains:

• A. Peptidoglycan
• B. Suberin
• C. Chitin✓
• D. Proteins

Explanation: The fungal cell wall is a complex and flexible structure composed basically of chitin, α- and β- linked glucans, glycoproteins, and pigments.

Q31. DNA synthesis takes place in which phase of the cell?

• A. G0
• B. G1
• C. G2
• D. S✓

Explanation: There are 4 phases of the cell cycle, namely G1 phase, S phase, G2 phase and M phase. During G1 phase or gap 1 phase, the cell increases in size. Also, various proteins are synthesized in this phase. During S phase or synthesis phase, the DNA replication takes place. During G2 phase, cell continues to grow until it enters the M phase or mitosis phase. Cell division takes place in M phase. Thus, the correct answer is 'S phase.'

Q32. The RNA found in Ribosomes is:

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

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

Q33. The outermost boundary in most of the leaf cell is:

• A. Cell wall✓
• B. Cell membrane
• C. Tonoplast
• D. Unit membrane
• E. Polar substances

Explanation: The plasma membrane is the common boundary between the cell and its environment in all cells but it is the outermost covering of the animal cells. The cell wall forms the outermost boundary of plant cells.

Q34. In humans,_ is responsible for producing cell's hydrogen peroxide.

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

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

Q35. The soluble part of the blood is called:

• A. Karyolymph
• B. Nucleoplasm
• C. Protoplasm
• D. Serum✓

Explanation: Option A: Karyolymph is the fluid portion of the nucleus of a cell. It is made up of water, salts, and dissolved proteins. Karyolymph does not contain any organelles, such as chromosomes or ribosomes. Option B: Nucleoplasm is another term for karyolymph. It is the fluid portion of the nucleus of a cell. Option C: Protoplasm is the living material that makes up cells. It is made up of water, proteins, carbohydrates, lipids, and nucleic acids. Protoplasm is not soluble in blood because it is a complex mixture of molecules that are held together by bonds. Option D: Serum is the liquid portion of blood that remains after blood cells and clotting factors have been removed. It is mostly water, but it also contains dissolved proteins, nutrients, hormones, and electrolytes. Serum is soluble in blood because it is a relatively simple mixture of molecules that are not held together by strong bonds.

Q36. The animals that feed on organic debris from decomposing plants and animals are called:

• A. Herbivores
• B. Carnivores
• C. Omnivores
• D. Detritivores✓

Explanation: Detritivores, also known as detritophages, detritus feeders, detritus eaters, or saprophages, are heterotrophs that obtain nutrients by consuming detritus (decomposing plant and animal parts as well as feces). By doing so, all these detritivores contribute to decomposition and the nutrient cycles.

Q37. Pinacocytes forms:

• A. Pores
• B. Ostia
• C. Epidermis✓
• D. Spongocoel

Explanation: Outer dermal layer of Porifera, pinacoderm, is formed of cells called Pinacocytes.

Q38. Actinia is the biological name of:

• A. Sea Anemone✓
• B. Corals Obelia
• C. Jellyfish
• D. Frog

Explanation: This is a fact. Actinia is the biological name of Sea Anemone. It is a Cnidarian.

Q39. The simplest form in Kingdom Animalia belongs to:

• A. Eumetazoa
• B. Bilateria
• C. Protozoa
• D. Parazoa✓
• E. Protostomia

Explanation: The simplest form in Kingdom Animalia belongs to ‘Parazoa’.

Q40. The Porifera are pore-bearing animals, commonly called:

• A. Corals
• B. Sponges✓
• C. Hydras
• D. Anemones

Explanation: The Porifera are pore-bearing animals, commonly called 'sponges'.

Q41. High level of _and _in the blood are the contributing factors in the formation of kidney stones.

• A. Calcium, Oxalate✓
• B. Calcium, magnesium
• C. Calcium, sodium
• D. Sodium, sulphate

Explanation: High level of calcium and oxalate in the blood are the contributing factors in the formation of kidney stones. Most kidney stones are formed when oxalate binds to calcium while urine is produced by the kidneys. The build-up of calcium oxalate can form crystals, which can form kidney stones.

Q42. Identify the correct order?

• A. Organ>function>cell>tissue
• B. Cell>organ>tissue>function
• C. Cell>tissue>organ>system✓
• D. Tissue>organ>cell>function

Explanation: The correct sequence of the structural organization of the human body is: Cell → tissue → organ → organ system.

Q43. Blood containing CO2 is:

• A. Red in color
• B. Blue in color
• C. Reddish purple in color✓
• D. Reddish blue in color

Explanation: When the oxygen is released, it is replaced by carbon dioxide, which is then taken back to our lungs and expelled from our bodies as we breathe. When carbon dioxide binds to hemoglobin, the color changes from bright red to dark red with a hint of purple .

Q44. The mechanism by which substances are removed from blood and are directly added to the tubular fluids is called:

• A. Glomerular filtration
• B. Excretion
• C. Tubular secretion✓
• D. Tubular reabsorption

Explanation: Kidneys filter blood in a three-step process. First, the nephrons filter blood that runs through the capillary network in the glomerulus. Almost all solutes, except for proteins, are filtered out into the glomerulus by a process called glomerular filtration. Second, the filtrate is collected in the renal tubules. Most of the solutes get reabsorbed in the PCT by a process called tubular reabsorption. In the loop of Henle, the filtrate continues to exchange solutes and water with the renal medulla and the peritubular capillary network. Water is also reabsorbed during this step. The collecting ducts collect filtrate coming from the nephrons and fuse in the medullary papillae. From here, the papillae deliver the filtrate, now called urine, into the minor calyces that eventually connect to the ureters through the renal pelvis.

Q45. Neurons CANNOT undergo division, because they do not have:

• A. Centrosome✓
• B. Nucleus
• C. Mitochondria
• D. Golgi apparatus

Explanation: Neurons cannot undergo division because they do not have centrosomes. Centrosomes are organelles that help to organize microtubules, which are essential for cell division. Without centrosomes, neurons cannot properly divide and therefore cannot repair themselves or replace damaged cells.

Q46. Hypothalamus initiates the release of hormones, by their releasing factors, while _ is directly released by it.

• A. TSH
• B. ACTH
• C. FSH
• D. Dopamine✓

Explanation: The hormones produced in the hypothalamus are corticotropin-releasing hormone, dopamine, oxytocin, growth hormone-releasing hormone, somatostatin, gonadotropin-releasing hormone and thyrotropin-releasing hormone.

Q47. Transport of glucose across the cell membrane occurs by:

• A. Simple diffusion
• B. Facilitated diffusion✓
• C. Osmosis
• D. Primary active transport
• E. Secondary active transport

Explanation: Glucose being neutral can pass through cell membranes easily by facilitated diffusion.

Q48. Which artery supplies blood to the liver?

• A. Pulmonary artery
• B. Hepatic artery✓
• C. Celiac artery
• D. Thoracic artery

Explanation: Hepatic artery supplies blood to the liver.

Q49. Movement of the hip joint is by which type of synovial joint?

• A. Gliding joint
• B. Ball and socket joint✓
• C. Pivot joints
• D. Hinge joint

Explanation: The different types of synovial joint are : (a) Ball and Socket joint : In this, the round end of one bone fits into the socket of the other bone. It allows free movement. Eg : Shoulder joint and hip joint. (b) Hinge joint : It moves only in a single plane. Eg. Elbow joint, ankle joint, knee joint. (c) Pivot joint : This joint is responsible for providing movement in one plane. Eg : Joint between atlas and axis, between radius and ulna. (d) Gliding joint/Plane Joint : It allows limited movement in all directions as the bones are closely packed together. Eg : joints between carpal bones and between the tarsal bones. (e) Saddle joint : Both ball and sockets are poorly developed and movement is comparatively less. Eg: Carpmetacarpal joint

Q50. A hormone called _controls the secretion of juice.

• A. Gastrin✓
• B. Secretin
• C. Thyroxin
• D. Iodothyronine
• E. Parathormone

Explanation: Gastrin is a peptide hormone that stimulates secretion of gastric acid (HCl) by the parietal cells of the stomach and aids in gastric motility. It is released by G cells in the pyloric antrum of the stomach, duodenum and pancreas.

Q51. Process of uncontrolled cell division is due to which one of the following reasons?

• A. DNA replication
• B. Mutations✓
• C. Translation
• D. Transcription

Explanation: Cancer is unchecked cell growth. Mutations in genes can cause cancer by accelerating cell division rates or inhibiting normal controls on the system, such as cell cycle arrest or programmed cell death.

Q52. Which of the following is derived from Latin word VENUME which means poisonous?

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

Explanation: The word virus is derived from LATIN word VENUME which means poisonous.

Q53. Functions of the brainstem include all of the following EXCEPT:

• A. Integration of righting reflexes
• B. Autonomic control for respiration
• C. Equilibrium and posture regulation
• D. Initiation of voluntary movements✓
• E. Fixation of the eyes

Explanation: The motor cortex is an area within the cerebral cortex of the brain that is involved in the planning, control, and execution of voluntary movements. It is not a part of the brainstem. The brainstem consists of midbrain, pons and medulla oblongata. Righting reflex is controlled by midbrain. The brainstem sends messages to the rest of the body and regulate balance, respiration, heart rate and many involuntary processes.

Q54. Cardiac output is increased by all of the following EXCEPT:

• A. Hypoxia
• B. Exercise
• C. Sleep✓
• D. Pregnancy
• E. Anemia

Explanation: Sleep decreases the cardiac output.

Q55. An enzyme that helps in the conversion of RNA to DNA is called:

• A. Transcriptase
• B. Polymerase
• C. Reverse transcriptase✓
• D. Synthetase

Explanation: The enzyme that helps in the conversion of RNA to DNA is called reverse transcriptase. It is a type of DNA polymerase that can synthesize DNA from an RNA template. Reverse transcriptase is found in retroviruses, which are a type of virus that uses RNA as its genetic material. When a retrovirus infects a cell, its reverse transcriptase enzyme converts the viral RNA into DNA, which is then integrated into the host cell's genome. This allows the virus to replicate and spread.

Q56. Sequence of stop codon in DNA is:

• A. TAG
• B. AUG
• C. UAG✓
• D. AAA
• E. AGT

Explanation: Each three-letter sequence of mRNA nucleotides corresponds to a specific amino acid, or to a stop codon. UGA, UAA, and UAG are stop codons.

Q57. The type of gene interaction in which the effect caused by gene at one locus interfere with the effect caused by another gene at another locus is known as:

• A. Pleiotropy
• B. Epistasis✓
• C. Polygenic Inheritance
• D. Gene linkage
• E. Crossing over

Explanation: Epistasis is the interaction between genes present at different loci. Geotype of one locus may alter of suppress the phenotypic expresion at another locus. As a result, different phenotypic ratios are expected.

Q58. Which one of the following pairs represent analogous feature?

• A. Elephant tusks and tunan incisors
• B. Telecost erythrocyte and mammalian erythrocyte
• C. Insect wing and bat wing✓
• D. Mole forelimb and hind wing
• E. Reptilian heart and mammalian heart

Explanation: Analogous Organs are those organs of different animals that although look different in structure but perform a common function. These organs are evolved from a convergent evolution.

Q59. The position of an organism in a food chain of an ecosystem is called:

• A. Level of ecosystem
• B. Food chain
• C. Food web
• D. Trophic level✓
• E. Energy pyramid

Explanation: Trophic level is defined as the position of an organism in the food chain and ranges from a value of 1 for primary producers to 5 for marine mammals and humans. The method to determine the trophic level of a consumer is to add one level to the mean trophic level of its prey.

Q60. Which of the following trophic levels has the largest biomass in ecosystems?

• A. Decomposers
• B. Primary consumer
• C. Sécondary consumer
• D. Producers✓
• E. Herbivores

Explanation: The trophic level that contains the greatest biomass in most ecosystems is the producers. Producers are organisms that are able to make their own food from sunlight or chemicals. Thus, they have access to 100% of the energy available. They use this energy to grow, repair, and reproduce, and only 10% of their energy is able to be passed on to the next level as a result. This pattern is called the 10% rule, and it makes less energy available to higher trophic levels. As a result, typically each trophic level has less biomass and less organisms than the level before it.

Q61. The zone with insufficient light to support photosynthesis in ecosystem is called:

• A. Oceanic sub-zone
• B. Limnetic zone
• C. Profundal zone✓
• D. Littoral benthic zone

Explanation: Profundal zone: Here, light is insufficient to support photosynthesis. The organisms of this zone are mainly nourished by detritus that falls from the littoral and limnetic zone and by incoming sediment. Decomposers and detritus feeders, such as, snails and certain insect larvae, bacteria, fungi and fishes, inhabit it.

Q62. Common cold is caused by:

• A. Adenovirus✓
• B. Retroviruses
• C. Herpes virus
• D. Bacteria
• E. Protozoans

Explanation: Common cold is caused by adenovirus.

Q63. Which of the following is caused by the bacteria T. pallidum and transmitted by sexual contact?

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

Explanation: The cause of syphilis is a bacterium called Treponema pallidum. The most common way syphilis is spread is through contact with an infected person's sore during sexual activity.

Q64. Electron Transport Chain (ETC) takes place in _ part of the mitochondria.

• A. Matrix of mitochondria
• B. Cytoplasm
• C. Outer membrane
• D. Inner membrane✓

Explanation: In eukaryotic organisms, the electron transport chain and site of oxidative phosphorylation is found on the inner mitochondrial membrane.

Q65. About how much of the total photosynthesis is carried out by aquatic plants?

• A. 90%✓
• B. 60%
• C. 50%
• D. 40%
• E. 10 %

Explanation: 90% of total photosynthesis is carried out by aquatic plants, chiefly algae (80% in oceans and 10% in freshwater).

Q66. The cyclic series of reactions by which carbon is fixed and reduced, resulting in the synthesis of sugar, during the dark reaction of photosynthesis is called:

• A. Kreb's cycle
• B. Citric acid cycle
• C. Melvin Calvin cycle✓
• D. Oxidative Phosphorylation

Explanation: The Calvin cycle is the term used for the reactions of photosynthesis that use the energy stored by the light-dependent reactions to form glucose and other carbohydrate molecules.

Q67. In aerobic respiration of glucose, total number of ATP is:

• A. 38✓
• B. 40
• C. 46
• D. 48
• E. 60

Explanation: Correct option is A: In aerobic respiration, the full oxidation of one glucose molecule can theoretically yield 38 ATP molecules. Refer to the table:

Q68. Golgi complex is involved in the formation of:

• A. Lysosomes✓
• B. RER
• C. Vacuoles
• D. SER

Explanation: The Golgi apparatus or Golgi complex is an organelle found in most eukaryotic cells. It is a collection and dispatch station for the protein products received from the endoplasmic reticulum. Its function also includes lipid transport and lysosome formation.

Q69. Which of the following is characterized by accumulation of lipids in the brain cells leading to mental retardation and even death?

• A. Grave’s Disease
• B. Addison’s disease
• C. Glycogenesis type II disease
• D. Tay-Sachs disease✓

Explanation: Tay-Sachs disease is characterized by the accumulation of lipids in the brain.

Q70. All of the following are present in myofilaments of muscle cells except:

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

Explanation: Tubulin is a protein found primarily in mircotubules.

Q71. Number of centrioles after completion of the G2 phase and during the metaphase of mitosis is _ and _ respectively.

• A. 2,2
• B. 2,4
• C. 4,4✓
• D. 4,2

Explanation: Number of centrioles after completion of the G2 phase and during the metaphase of mitosis is 4 and 4 respectively. During S phase of the cell cycle, the centrosomes replicate. Each centrosome contains 2 centrioles. Since now there are 2 centrosomes, the total number of centrioles will be 4. G2 phase comes right after the S phase and during metaphase cytokinesis has not occured as a result, the cell contains 4 centrioles in both of these stages.

Q72. In a cross-section, each centriole consists of nine triplets of:

• A. Microfilaments
• B. Intermediate filaments
• C. Microtubules✓
• D. Microvilli

Explanation: Centrioles are cylindrical structures typically composed of nine triplet of microtubules.

Q73. Myelin Sheath is produced by:

• A. Schwann cells and astrocytes
• B. Oligodendrocytes and osteoclasts
• C. Osteoclasts and astrocytes
• D. Schwann cells and oligodendrocytes✓

Explanation: Myelin is formed by Schwann cells in the peripheral nervous system (PNS) and oligodendrocytes in the central nervous system (CNS).

Q74. Destruction of the anterior horn of the spinal cord would lead to a loss in:

• A. Commissural impulses
• B. Integrating impulses
• C. Sensory impulses
• D. motor impulses✓

Explanation: Destruction of anterior horn cells of spinal cord results in loss of myelinated axons in the anterior roots and motor nerves. Thus this results in denervation of muscle fibres and loss of voluntary motor impulses.

Q75. GnRH, a hypothalamic hormone, needed in reproduction, acts on:

• A. Anterior pituitary gland and stimulates secretion of LH and FSH✓
• B. Posterior pituitary gland and stimulates secretion of oxytocin and FSH
• C. Ovaries and stimulates secretion of estrogen and progesteron
• D. Posterior pituitary gland and stimulates secretion of LH and relaxin

Explanation: The hypothalamus produces GnRH, which is a gonadotropin hormone. It promotes the release of LH and FSH from the anterior pituitary, which aids in the development of the gonads. LH and FSH are hormones that regulate reproductive activity in both male and female gonads.

Q76. A temporary gland in the human body is:

• A. Corpus caradiacum
• B. Corpus luteum✓
• C. Corpus allatum
• D. Pineal Gland

Explanation: Corpus luteum is a temporary gland in the human body. After ovulation, the Graafian follicle transforms into corpus luteum, which secretes progesterone. In the absence of fertilization, corpus luteum degenerates.

Q77. The posterior pituitary gland is not a “true” endocrine gland because:

• A. It is provided with a duct
• B. It only stores and releases hormones✓
• C. It is under the regulation of hypothalamus
• D. It secretes enzymes

Explanation: Oxytocin and vasopressin hormones are produced by the hypothalamus but stored and are released into the bloodstream via the posterior pituitary. That's the reason why it is not a true endocrine gland. Endocrine glands are the ductless glands that secrete and release hormones in the blood directly.

Q78. The amino acid tryptophan is a precursor for:

• A. Estrogen and progesterone
• B. Cortisol and cortisone
• C. Melatonin and serotonin✓
• D. Thyroxine and triiodothyronine

Explanation: The amino acid tryptophan is the precursor for the synthesis of melatonin and serotonin. Both melatonin and serotonin regulate various functions inside our body, such as appetite, mood and sleep.

Q79. A chemical signal that has both, endocrine and neural roles is:

• A. Epinephrine✓
• B. Cortisol
• C. Melatonin
• D. Calcitonin

Explanation: Epinephrine is released by sympathetic postganglionic neurons (the adrenergic neurons) and serves as a neurotransmitter. Epinephrine also serves as an emergency hormone of adrenal medulla and prepares the body for fight or flight response by intensifying the effect of sympathetic stimulation.

Q80. The filterable agents were first purified in 1935, when Stanley was successful in crystallizing the _.

• A. Polio virus
• B. Tobacco mosaic virus✓
• C. Hepatitis virus
• D. Influenza virus

Explanation: The purification and crystallization of a filterable agent, namely the tobacco mosaic virus (TMV), were achieved by Wendell Meredith Stanley, but the year of this accomplishment is often noted as 1935. In 1935, Wendell Stanley successfully crystallized the tobacco mosaic virus, which was a groundbreaking achievement. This work contributed to the understanding of viruses as distinct entities and laid the foundation for the study of their structure and composition.

Q81. Volume of bacteriophage is about _ of host.

• A. 1/10 times
• B. 1/100 times
• C. 1/100 times
• D. 1/1000 times✓

Explanation: The volume of a bacteriophage is typically much smaller than the volume of its host bacterial cell. Bacteriophages are viruses that infect and replicate within bacteria. The size of bacteriophages 1/1000 smaller than the bacterial cells they infect.

Q82. Van Neil hypothesis about the production of oxygen during photosynthesis was based on the study and investigations on:

• A. Bacteria✓
• B. Algae
• C. Protonema
• D. Cyanobacteria

Explanation: Using evidence from bacteria that utilize hydrogen sulfide (H2S) for photosynthesis, van Niel hypothesized that all photosynthetic organisms need a hydrogen source and that plants split water as their hydrogen source, releasing oxygen. Scientists confinned this hypothesis by using a heavy isotope of oxygen (O18).

Q83. Location of photosynthetic pigments in purple sulphur bacteria:

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

Explanation: Some bacteria are photosynthetic but they lack chloroplast. Their photosynthetic pigments are present in cytoplasm of cell. In purple sulfur bacteria the photosynthetic pigments such as, bacteriochlorophylls and caretinoids are located in the cytoplasm rather than within specialised membrane structure such as chloroplast. These pigments are dispersed through out the cytoplasmic region of bacteria and are responsible for capturing light energy during photosynthesis.

Q84. Due to higher heat capacity and H-bonds, water acts as:

• A. Thermo-stabilizer✓
• B. Solvent
• C. Inert medium
• D. Reactive medium

Explanation: Thermo-stabilizer: Water acts as a thermo-stabilizer due to its high heat capacity. Heat capacity refers to the amount of heat energy required to raise the temperature of a substance. Water has a relatively high heat capacity, which means it can absorb and store a significant amount of heat energy without a substantial increase in temperature. This property of water allows it to stabilize temperature changes in its surroundings. It helps regulate the Earth's climate by absorbing heat during the day and releasing it at night, preventing rapid temperature fluctuations. Additionally, water's high heat capacity plays a crucial role in maintaining stable temperatures within living organisms, protecting them from extreme temperature variations. Solvent: Water is often called the "universal solvent" due to its ability to dissolve a wide variety of substances. This property arises from water's polarity and its ability to form hydrogen bonds. Water molecules have a partially positive hydrogen end and a partially negative oxygen end, which makes them attracted to other polar or charged molecules. When a solute is added to water, the water molecules surround and separate the solute particles, allowing them to disperse evenly throughout the water. This ability to dissolve and transport various substances makes water a vital solvent for biological processes, such as nutrient transport in cells and the dissolution of biomolecules like proteins and carbohydrates. Inert medium: Water is not considered an inert medium. An inert medium refers to a substance that does not react chemically with other substances. Water, on the other hand, can participate in chemical reactions due to its polar nature and ability to form hydrogen bonds. It can act as a reactant or a product in various chemical reactions, including acid-base reactions, hydrolysis reactions, and oxidation-reduction reactions. Reactive medium: While water can participate in chemical reactions, it is not primarily known for being a reactive medium. Water is relatively stable and does not readily undergo spontaneous reactions. However, under certain conditions, such as in the presence of catalysts or specific reactants, water can participate in chemical reactions, such as hydrolysis or dehydration reactions. These reactions typically involve breaking and forming covalent bonds within water molecules and other compounds. In summary, among the given options, a) Thermo-stabilizer is the most accurate description of water's role due to its high heat capacity. However, it is essential to note that water is also a solvent and can participate in chemical reactions under specific conditions, but it is not considered an inert or reactive medium by default.

Q85. The bond that is formed between two monosaccharide units is called:

• A. Ionic bond
• B. Hydrogen bond
• C. Peptide bond
• D. Glycosidic bond✓

Explanation: Ionic bond: An ionic bond is a type of chemical bond that forms between two atoms when one atom donates an electron, becoming positively charged (cation), and the other atom accepts the electron, becoming negatively charged (anion). Ionic bonds occur between atoms with significantly different electronegativities, resulting in the transfer of electrons. Hydrogen bond: A hydrogen bond is a type of weak chemical bond that occurs between a hydrogen atom in a polar covalent bond and an electronegative atom (usually oxygen, nitrogen, or fluorine) in another molecule. Hydrogen bonding is important for the structure and properties of many molecules, but it is not the bond that forms between two monosaccharide units. Peptide bond: A peptide bond is a specific type of covalent bond that forms between the carboxyl group (COOH) of one amino acid and the amino group (NH2) of another amino acid during the formation of a protein. Peptide bonds are essential for building protein chains in a process called protein synthesis.Glycosidic bond: The correct option is glycosidic bond. A glycosidic bond is a type of covalent bond that forms between two monosaccharide units during the formation of disaccharides, oligosaccharides, and polysaccharides. It is formed when a hydroxyl group (-OH) of one monosaccharide reacts with the anomeric carbon (the carbon containing the carbonyl group) of another monosaccharide. This reaction involves the removal of a water molecule (H2O), resulting in the formation of a glycosidic linkage between the two monosaccharides.In summary, option d) Glycosidic bond is the correct option. A glycosidic bond is the covalent bond that forms between two monosaccharide units during the formation of various types of saccharides like disaccharides, oligosaccharides, and polysaccharides. The other options (a) Ionic bond, (b) Hydrogen bond, and (c) Peptide bond are different types of chemical bonds with different functions and properties.

Q86. The layers of cellulose fiber in cell wall are arranged with each other at:

• A. Obtuse angle
• B. Parallel angle
• C. Right angle✓
• D. Horizontal angle

Explanation: Cellulose fibers are responsible for strengthening of cell wall of plants. They are arranged in a criss-cross manner and placing these fibers at right angles with each other gives more strength.

Q87. Cellulose is usually not found in:

• A. Primary cell wall
• B. Secondary cell wall
• C. Middle lamella✓
• D. All contain cellulose

Explanation: Cellulose is present in both primary cell wall and secondary cell wall. Middle lamella is composed of sticky, gel-like magnesium and calcium salts (pectates) and pectin.

Q88. Which of the following produce response?

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

Explanation: Effector is a structure or organ that brings about an action of 'effect' as a result of a stimulus received through a receptor which can come from the CNS or from a hormone.

Q89. Which of the following is associated with sense of touch?

• A. Paccinian's corpuscles
• B. Mechanoreceptors
• C. Merkel disks
• D. Both B and C✓

Explanation: Merkel disks are touch receptors. Receptors for touch and pressure are also called Mechanoreceptors. Thus, option D is the correct answer.

Q90. All enzymes are _.

• A. Fibrous proteins
• B. Lipoproteins
• C. Low molecular weight proteins
• D. Globular proteins✓

Explanation: Enzymes are composed of hundreds of amino acids joined together and coiled upon themselves to form a globular structure.

Q91. On the hydrogen atom spectrum, a series of spectral lines that fall within the visible region is:

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

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

Q92. For a chemical reaction A & B the threshold energy of the reaction is 31 kJ/mole. The average internal energy of A is 12 kJ/mole. What will be the activation energy of A?

• A. 43 kJ/mole
• B. 37 kJ/mole
• C. 25 kJ/mole
• D. 19 kJ/mole✓

Explanation: Threshold energy = Activation energy + normal energy of reactant31 = A + 12A = 19 kJ/mole

Q93. By raising the temperature 1°C, conductance increases by 2 to 2.5%. Which is due to reduced _ of ions?

• A. Hydration✓
• B. Neutralization
• C. Hydrolysis
• D. Ionization

Explanation: Hydration is inversely propotional to conductance. In hydration, ions are surrounded by water molecules so their conductance decreases. So, in order to increase conductance, hydration must decrease to allow electron flow (to conduct electricity).

Q94. s-sp3 overlap occurs in _ molecule.

• A. Cl2
• B. CH4✓
• C. HF
• D. HI

Explanation: Each sp3 hybrid orbital of carbon overlaps 1s-orbital of hydrogen to form C-H sigma bonds.

Q95. ΔH = ΔE+PΔV is the change in enthalpy at constant_.

• A. Volume
• B. Pressure✓
• C. Temperature
• D. Mass

Explanation: At a constant pressure, the heat flow for any process is equal to the change in the internal energy of the system plus the work done (PV).

Q96. As the concentration of reactant increases, the rate of reaction also increases, it is because:

• A. K.E. increases in molecules
• B. Oscillation increases between molecules
• C. Collisions frequency increases✓
• D. Temperature of molecules increases

Explanation: Collisions frequency increases: The frequency of collisions between reactant particles is the number of collisions that occur per unit time. The frequency of collisions increases with increasing concentration because there are more reactant particles present in the same volume. This is the main reason why the rate of reaction increases with increasing concentration.

Q97. The equation shows the reaction between element X and dilute hydrochloric acid. What types of bonding are present in element X and in compound XCl2? X(s) + 2HCI(aq) → XCI(aq) + H2 (g)

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

Explanation: Since hydrogen is released, we can assume that X is an electropositive element, almost surely a metal, so X will have metallic bonding. For the next part, since X is a metal, XCl will have ionic bonding since almost all metal compounds form ionic bonds and not covalent.

Q98. If the value of Kc is very large then it shows that _completed.

• A. Forward reaction✓
• B. Reverse reaction
• C. Equilibrium is maintained
• D. Kc is moderate

Explanation: Kc=[product]/[reactant], now if the Kc value is very large, we can use the equation to conclude that the concentration of products are higher than reactants, depicting that the forward reaction has completed or is near completion.

Q99. For stable molecular geometry, each carbon atom undergoes:

• A. sp hybridization✓
• B. sp2 hybridization
• C. sp3 hybridization
• D. dsp3 hybridization
• E. d2sp2 hybridization

Explanation: Carbon can undergo all three hybridization i.e. sp, sp2 and sp3. Carbon can have an sp hybridization when it is bound to two other atoms with the help of two double bonds or one single and one triple bond. This results in linear arrangement and bond angle of 180°. A carbon atom is sp2 hybridized when bonding takes place between 1 s-orbital with two p orbitals. There is a formation of two single bonds and one double bond between three atoms. This reults in trignol arrangement with bond angles of 120° A carbon atom is sp3 hybridized when it is bonded to four other atoms. Here, 1 s orbital and 3 p orbitals in the same shell of an atom combine to form four new equivalent orbitals. This results in is tetrahedral with a bond angle of 109.5° The order of strength of CH bonds is sp>sp2>sp3.

Q100. If the absolute temperature of a gas is reduced to one half and the pressure is doubled, the volume of gas will be:

• A. Increased four times
• B. Decreased four times✓
• C. Remained unchanged
• D. Reduced to one half
• E. Increased two times

Explanation: PV=nRT V=nRT/P If temperature is halved and pressure is doubled then V=n x R x 0.5T/2P = V=¼(nRT/P) Hence, volume is decreased four times.

Q101. Change in extensive property is proportional to the _of material.

• A. Temperature
• B. Volume
• C. Quantity✓
• D. Pressure

Explanation: The value of an extensive property is directly proportional to the amount of matter in question. If the property of a sample of matter does not depend on the amount of matter present, it is an intensive property.

Q102. Which of the following has the highest electrical conductivity?

• A. Aqueous sugar solution
• B. Solid graphite✓
• C. Solid sodium chloride
• D. Gaseous carbon dioxide

Explanation: Graphite is an allotrope of carbon and is known for its high electrical conductivity. The carbon atoms in graphite are arranged in a layered structure, forming sheets of hexagonal rings. These sheets have delocalized electrons that can move freely along the layers, allowing for efficient electron flow and high electrical conductivity. Therefore, solid graphite has a high electrical conductivity.

Q103. The oxidation number of nitrogen in the HNO3 is _.

• A. 4+
• B. 5+✓
• C. 6+
• D. 7+

Explanation: This is the following solution.

Q104. X is a salt that decomposes in water. What is the reason for its decomposition? e- + X3+ → X2+ E cell = 1.91 V

• A. This potential oxidises salt
• B. This potential reduces salt✓
• C. This potential reduces water
• D. This potential oxidises water

Explanation: Reduction is can be defined as gain of electrons. Since the salt is gaining an electron, it is being reduced.

Q105. In acidic medium, oxidation action of potassium permanganate depends upon:

• A. Mn7+✓
• B. KMnO2+
• C. MnO2
• D. Mn1+
• E. Mn4+

Explanation: Equation for reduction of KMnO4 in acidic medium:8H+ + MnO4- + 5e- ----> Mn2+ + 4H2OHere in MnO4- the oxidation state of Mn is +7, and it is being reduced to Mn2+Therefore, it acts as an oxidising agent as Mn7+ can gain elections from the substance being oxidised and get reduced itself.

Q106. The energy required to remove the outermost electron from a gaseous atom Is called:

• A. Electronegativity
• B. Electropositivity
• C. Ionisation energy✓
• D. electron affinity

Explanation: Ionization energy, also called ionization potential, is the amount of energy required to remove one mol of electron from an isolated atom or molecule.

Q107. Which sequence of reaction conditions should be used to produce the compound below from benzene?

• A. AlCl3 / Cl2 ; H2 / Rh / C✓
• B. Cl2 / UV light ; H2 / Rh / C
• C. H2 / Rh / C ; AlCl3 / Cl2
• D. HCl ; H2 / Rh / C

Explanation: A would be the answer as we have electrophilic substitution taking place involving the formation of a Cl+ ion which is formed via the interaction of AlCl3 catalyst and Cl2 gas producing (AlCl4)- and Cl+. The Cl+ replaces Hydrogen from the benzene ring. Once chlorobenzene is formed, it is reduced by H2 gas and rhodium catalyst. Reducing the benzene ring first would form a cycloalkane and then, using AlCl3 + Cl2 would do nothing.

Q108. Cyanohydrins can be synthesised from ketones through:

• A. Nucleophilic addition reaction✓
• B. Unimolecular nucleophilic substitution reaction
• C. Electrophilic substitution reaction
• D. Bimolecular nucleophilic substitution reaction
• E. Nucleophilic elimination reaction

Explanation: A cyanohydrin reaction is an organic chemical reaction by an aldehyde or ketone with a cyanide anion or a nitrile to form a cyanohydrin. This is a base-catalysed nucleophilic addition reaction.

Q109. Which of the following elements does not belong to the f-block of elements?

• A. Uranium
• B. Samarium
• C. Thorium
• D. Osmium✓

Explanation: All the elements belong in f-block except Osmium which belongs to the d-block.

Q110. Gasoline is a mixture of hexane and _.

• A. Methane
• B. Butane
• C. Decane
• D. Heptane✓

Explanation: Heptane and Hexane are both components of gasoline.

Q111. What is the name of the following compound?

• A. 1-Ethyl-3, 4 - dimethylcycloheptane
• B. 2-Ethyl-4, 5-dimethylcyclohexane
• C. 1-Ethyl - 4, 4-dimethylcyclohexane
• D. 4-Ethyl-1, 2 - dimethylcyclohexane✓

Explanation: Apply rules of nomenclature. The adjacent methyl groups will be preffered first because they are closer compared to ethyl and methyl groups.

Q112. Bakelite is a polymer of formaldehyde and _.

• A. Phenol✓
• B. Ethanol
• C. Butanol
• D. Methanol

Explanation: Bakelite is a condensation polymer of formaldehyde and phenol. In practice, the phenol and formaldehyde are first polymerized to a small extent by using the proper choice of catalyst and temperature.

Q113. To avoid the formation of toxic compounds with substance _ is used for disinfecting water.

• A. KMNO4
• B. Chloramines
• C. O3✓
• D. Alums

Explanation: Ozone has a greater disinfection effectiveness against bacteria and viruses compared to chlorination. In addition, the oxidizing properties can also reduce the concentration of iron, manganese, sulfur and reduce or eliminate taste and odor problems.

Q114. Cannizzaro's reaction is NOT given by:

• A. Formaldehyde
• B. Acetaldehyde✓
• C. Benzaldehyde
• D. Trimethyl acetaldehyde

Explanation: Cannizzaro's reaction is not given by aldehydes and ketones that have alpha hydrogen (hydrogen next to carbonyl carbon). In formaldehyde, there are no α Hydrogen so it will undergo this reaction. Acetaldehyde has 3 α Hydrogens next to C=O group so it cannot undergo this reaction. In trimethyl acetaldehyde, 3 CH3​ groups are attached to α Carbon and no α Hydrogen so it will undergo this reaction. In benzaldehyde, there is benzyl group on α carbon so it does not have α Hydrogen and it will undergo this reaction.

Q115. Which one of the following is called animal starch?

• A. Amylose
• B. Cellulose
• C. Glycogen✓
• D. Glycine

Explanation: Glycogen Is known as animal starch. The animals have polymerized glucose stored in the form of glycogen. Glycogen is stored in the hepatic cells in the liver. Starch obtained from plants to the animals is stored in the animal body in the form of glycogen.

Q116. Enzymes are _that catalyze chemical reactions in living organisms and are very specific in their action:

• A. Proteins✓
• B. Vitamins
• C. Lipids
• D. Minerals

Explanation: Enzymes are proteins that help speed up metabolism, or the chemical reactions in our bodies.

Q117. HCOOH is the structure of:

• A. Acetic acid
• B. Formic acid✓
• C. Valeric acid
• D. Caproic acid

Explanation: Formic acid, systematically named methanoic acid, is the simplest carboxylic acid, and has the chemical formula HCOOH.

Q118. The reaction CHCH + H2O +3{O} shows the formation of _.

• A. Acetic acid
• B. Picric acid
• C. Oxalic acid✓
• D. Formic acid

Explanation: Ethyne gets oxidised to oxalic acid.

Q119. In composition of natural gas, 0.17% is constituted by:

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

Explanation: Natural gas has Methane and ethane contributing to large portions with Methane being 90%, approximately, and ethane, up to 5%. The remaining being propane and butane exist in small proportions. As propane is not given as an option, we can safely assume our answer to be butane as Nitrogen is not found in natural gas.

Q120. By the fermentation process of starch and by the catalytic action of enzyme, _ is produced.

• A. Methyl alcohol
• B. Ethyl alcohol✓
• C. Acetyl alcohol
• D. Methanal

Explanation: Ethyl alcohol or ethanol is produced by the fermentation of starch.

Q121. Methyl ketones can be characterised by performing:

• A. Iodoform test✓
• B. Schiff’s test
• C. Benedict's reagent test
• D. Tollen's test
• E. Cannizzaro test

Explanation: When methyl ketone is heated with iodine in the presence of sodium hydroxide, yellow precipitate of iodoform is obtained. Hence, methyl ketones are characterized by iodoform test. In this reaction, methyl ketone is converted to the sodium salt of carboxylic acid.

Q122. In RNA, which of the bases is replaced by uracil?

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

Explanation: Uracil forms a nucleoside with only ribose sugar while thymine forms the same with only deoxyribose sugar. Other nitrogen bases (i.e. adenine, guanine, cytosine) produce nucleosides with both sugars.

Q123. In the atmosphere, CO2 is about:

• A. 0.01％
• B. 0.03％✓
• C. 0.05％
• D. 0.09％

Explanation: Carbon dioxide composes only about 0.03%-0.04% of the atmosphere. Oxygen is about 21% of our atmosphere. The vast bulk of our atmosphere is made up of nitrogen (78%).

Q124. Chlorophyll is a naturally occurring macromolecule that contains:

• A. Mg2+✓
• B. Al3+
• C. Fe3+
• D. B3+

Explanation: In chlorophyll, the central ion is magnesium, and the large organic molecule is a porphyrin.

Q125. The reactions of below diagram with RMgX leads to the formation of:

• A. RCHOHR
• B. RCHOHCH3
• C. R3CHCH3OH
• D. RCH2CH2OH✓

Explanation: Refer to the diagram.

Q126. Alkyl halides can also be obtained by halogenation of_.

• A. Alcohols
• B. Alkenes
• C. Alkanes✓
• D. Ketones

Explanation: The reaction of a halogen with an alkane in the presence of ultraviolet (UV) light leads to the formation of a haloalkane (alkyl halide).

Q127. Which of the following is necessary for the normal development of leaves and bark of the plants?

• A. Sodium
• B. Aluminium
• C. Calcium✓
• D. Beryllium

Explanation: Calcium plays an important role in producing plant tissues and it enables plants to grow better.

Q128. Which of the following fertilizers has the maximum percentage of nitrogen in a solid state?

• A. Ammonia
• B. Urea✓
• C. Di-ammonium hydrogen phosphate
• D. Ammonium nitrate

Explanation: Urea has the highest nitrogen content of all solid fertilizers at 46% Nitrogen.

Q129. At standard conditions of temperature and pressure, the ratio of volume of 18g H2O to the volume of 4.4g CO2 will be:

• A. 10:1✓
• B. 1:2
• C. 2:3
• D. 3:2
• E. 2:1

Explanation: No of moles=mass in g/MrMoles of water = 18/18 =1 mol 1mol=24dm3 so volume of water is also 24dm3 Moles of CO2= 4.4/44 = 0.1 moles0.1x24= 2.4dm324:2.410:1

Q130. Rutherford's atomic model failed because:

• A. It did not account for the stability of atom.✓
• B. It did not account for the attraction b/w protons and neutrons.
• C. The atom did not have neutrons.
• D. None of these.

Explanation: Rutherford’s model proposed that the negatively charged electrons surround the nucleus of an atom. He also claimed that the electrons surrounding the nucleus revolve around it with very high speed in circular paths. He named these circular paths as orbits. He also stated that electrons being negatively charged and nucleus being a densely concentrated mass of positively charged particles are held together by a strong electrostatic force of attraction. However, Rutherford's Model did not have any explanation regarding the stability of atoms and arrangement of electrons in an atom.

Q131. The second and third period contain:

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

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

Q132. Cathode rays travel in discharge tube from:

• A. Anode to cathode
• B. Cathode to anode✓
• C. Glass tube to vacuum pump
• D. Cathode through air

Explanation: Cathode rays come from the cathode because the cathode is charged negatively. So, those rays strike and ionize the gas sample inside the container. Therefore, cathode rays travel in discharge tube from cathode to anode.

Q133. The subshell which has only one orbital is identified by the letter:

• A. s✓
• B. d
• C. p
• D. f

Explanation: S orbital has only 1 orbital and is defined by letter S.

Q134. Sodium amalgam is an alloy of:

• A. Sodium and mercury metals✓
• B. Sodium and lead
• C. Sodium and zinc
• D. None

Explanation: Sodium Mercury Amalgam is a alloy of sodium and mercury metals that functions as a strong reducing agent in chemical synthesis.

Q135. Elements which have completely filled outermost shell and do not combine with other elements are called:

• A. Metal elements
• B. Reactive elements
• C. Unstable elements
• D. Rare earth elements✓

Explanation: Rare Earth elements are those which rarely combine with other elements to form compounds and are unreactive. They are a set of 17 metallic elements;including the 15 lanthanides along with Scandium and Yttrium and are further classified as heavy and light rare Earth elements.

Q136. The Balmer series lies in the:

• A. UV region
• B. Visible spectrum✓
• C. Infrared region
• D. None of the above

Explanation: Balmer series lies in the visible region of electromagnetic spectrum.

Q137. If an ideal gas has volume V at 27°C and it is heated at constant pressure so that it volume become 1.5V, the value of final temperature is:

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

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

Q138. An electron is moving along the axis of a solenoid carrying a current. Which of the following is a correct statement about the electromagnetic force acting on the electron?

• A. The force acts radially inwards
• B. The force acts radially outwards
• C. The force acts in the direction of motion
• D. No force acts✓

Explanation: The question states along the axis of a solenoid. This implies that the Magnetic feild is parallel to the direction of current (For magnetic force to act, it is necessary that the direction of current and magentic feild are perpendicular to eachother) Therefore, no force acts and electron moves straight through without getting deflected.

Q139. The magnetic lines of force are directed in a manner that they:

• A. Originate at south pole and terminate at north pole
• B. Pass through the magnet
• C. Originate at north pole and terminate at south pole✓
• D. Go away from both the poles

Explanation: It is clearly depicted in the image that magnetic field lines oiginate at north pole and terminate at the south pole.

Q140. What happens to the pressure of a sample of helium gas if the temperature is increased from 200 K to 800 K with no change volume?

• A. Pressure increases by a factor of 4✓
• B. Pressure decreases by a factor of 4
• C. Pressure decreases by a factor of 2
• D. Pressure increases by a factor of 2
• E. No change in pressure

Explanation: According to combined gas law, P1V1/T1 = P2V2/T2, The volume is constant so we can say that pressure and temperature are directly propotional. From 200K to 800K, the temperature increases four times (200x4=800) and since the pressure and temperature are directly propotional to eachother, the pressure also increases by a factor of 4.We all know ideal gas equation,Easy way to solve such questions PV = nRTHere V is given constant ( no change)for a sample n is also constantR is general gas constant So pressure is directly proportional to temperature So ratio will beP1/ P2 = T1/ T2We have to find P2 as they said after change in temperatureT1 = 200 KT2= 800 KPut,P1/ P2 = 200 / 800P1/ P2 = ¼Cross multiplying 4P1 = P2As we see the final pressure is 4 times the initial pressure , So ,Pressure increases by a factor of 4There's another method to solve We know ,T1 = 200 KT2= 800 KWe can write T2 asT2 = 4 × 200 But 200 K is T1 So we can write T2 = 4 × T1 Means that the final temperature is increased 4 times the initial temperature.But we also know Pressure is directly proportional to temperature If temperature is increases by 4 times, obviously pressure will also be increased by 4 times

Q141. Which of the following is a dimensionless quantity?

• A. Power
• B. Frequency
• C. Refractive Index✓
• D. Impulse

Explanation: Refractive index of a medium is the ratio of the speed of light in a vacuum to the speed of light in that particular medium. Since the speed of light in vacuum and the speed of light in different mediums have the same dimensions, a quantity which is the ratio of these two will be dimensionless. Therefore, option C is the correct answer.For power, the formula is Energy/time and its dimensions are ML2T-3 .For frequency, the formula is 1/time period and its dimension is T-1.For impulse, the formula is force x time and its dimensions are MLT-1 . So amongst all four, only refractive index is the one having no dimensions.

Q142. Alpha rays are nuclear radiation. They are the same as the _ nuclei.

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

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

Q143. When two bodies move towards each other with constant speed, the distance between them decreases at the rate 6m/sec. If they move in the same direction, the distance between them increases at the rate of 4 m/sec. Calculate their velocities.

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

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

Q144. Two capacitors C1 (6µF) and C2 (12µF) are in series across a 180 volts D.C supply. Calculate the charges on C1 and C2 respectively.

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

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

Q145. Three resistors of 6 ohms each, can be connected in all possible ways. The highest value of resistance that can be obtained (in ohms) is:

• A. 2 Ohms
• B. 4 Ohms
• C. 9 Ohms
• D. 18 Ohms✓
• E. 36 Ohms

Explanation: If we connect all three in series, combined resistance will be 6+6+6=18(Series combination always gives the highest combined resistance)If we connect all three in parallel, combined resistance will be 1/6 + 1/6 + 1/6 = 1/R so R = 2 Ohms(This is the lowest possible combined resistance)This cancels options A, B, C and E since the highest possible resistance must be equal 18 Ohms.

Q146. When the reverse bias of a pn junction diode is increased, a stage comes when the electric field setup is sufficient to rupture the bonds and release a large number of holes and electrons breakdown. This phenomenon is known as:

• A. Avalanche effect
• B. Zener effect✓
• C. Early effect
• D. High-field emission

Explanation: In reverse bias, if voltage is increased, due to available energy, a covalent bond breaks, and a large number of electrons are released. This causes a sudden increase in current. This is called the Zener effect. If reverse bias is increased further after the Zener effect, minority charge carriers attain high velocity and break down the bound electrons from covalent bonds, and the current increases. This is known as the Avalanche effect. The question asks about the release of electrons due to an electric field which is the Zener effect.

Q147. The magnetic field, B, produced in a solenoid depends on:

• A. Its length
• B. Its length and current in it
• C. Its length and number of turns in it
• D. Its length, number of turns and current in it✓

Explanation: Inside a solenoid, B=μ0IN/Lwhere I is the current,N is the no. of turns L is length Therefore, magnetic field inside a solenoid depends on all these factors.

Q148. Equation of continuity is expressed as:

• A. A1V2 = A2V1
• B. A1V1 = A2V2✓
• C. A1H2 = A2H1
• D. A1H1 = A2H2

Explanation: Option A: A1V2 = A2V1: This is the equation of continuity for fluid flow. It states that the mass flow rate through a control volume is constant. In other words, the amount of fluid that enters the control volume must equal the amount of fluid that leaves the control volume. Option B: The equation of continuity is expressed as A1V1 = A2V2. This equation states that the mass flow rate through a control volume is constant. In other words, the amount of fluid that enters the control volume must equal the amount of fluid that leaves the control volume. Option C: A1H2 = A2H1: This is the equation of continuity for heat transfer. It states that the heat flow rate through a control volume is constant. In other words, the amount of heat that enters the control volume must equal the amount of heat that leaves the control volume. Option D: A1H1 = A2H2: This is not the equation of continuity for heat transfer. It states that the product of the cross-sectional area and the heat transfer coefficient is constant. This is only true for steady-state heat transfer, which means that the temperature of the fluid does not change.

Q149. The path difference for the constructive interference is:

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

Explanation: The equation for constructive interferene is L = nλ.

Q150. The light exhibits the phenomena of constructive interference under the situation when it is _ and _.

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

Explanation: For constructive interference to take place, the waves must be monochromatic (single frequency) and integral multiple of pi or 180 degrees (which implies they must be in phase).

Q151. The distance between two consecutive antinodes is equal to:

• A. λ/8
• B. λ/6
• C. λ/4
• D. λ/2✓

Explanation: The distance between two consecutive antinodes (or two consecutive nodes) is equal to half a wavelength as shown:

Q152. The charge on the neutron is:

• A. 1.6 x 10-27 C
• B. Zero✓
• C. 1.6 x 10-31 C
• D. 9.11 x 10-19 C
• E. 9.6 x 10-15C

Explanation: A neutron is an electrically neutral sub-atomic particle. Therfore, it has no charge.

Q153. When applied stress changes the volume, the change in volume per unit volume is known as:

• A. Polymetric strain
• B. Crystalline strain
• C. Volumetric strain✓
• D. Equal strain

Explanation: The change in volume per unit volume is known as volumetric strain. It is a measure of how much the volume of a material changes in response to an applied stress. The volumetric strain is calculated as the change in volume divided by the original volume.

Q154. When a fluid is incompressible, it means:

• A. No internal frictional force
• B. Independent of coordinates
• C. Independent of time
• D. Its density remains constant✓
• E. Its density remains variable

Explanation: When a fluid is incompressible, it means, its volume or density does not change with changes in pressure.

Q155. In medical diagnosis for precise internal imaging of the brain, _ radiographs are used.

• A. X-ray
• B. Beta-ray
• C. Gamma-ray✓
• D. Alpha-ray

Explanation: For internal imaging of braina gamma rays are used.

Q156. A steady current of 5 A is drawn from an electric source at a voltage of 100 V. The power consumed (in Watts) is:

• A. 0.05W
• B. 5W
• C. 500W✓
• D. 50000W

Explanation: P=IVP=5Ax100VP=500W

Q157. S.I. Unit of rate of flow of a fluid =

• A. m/sec
• B. m2/sec
• C. m3/sec✓
• D. m3/sec2

Explanation: Rate of flow of a fluid implies the volume flow rate. Therefore, the answer is C.

Q158. The level of radiation to which the human body can be exposed is _ times the radiation from natural sources.

• A. 1 to 10✓
• B. 10 to 100
• C. 10 to 1000
• D. 10 to 10000

Explanation: This is the range to which the human body can be exposed. Greater than this range can be fatal for the human body.

Q159. Conversion of heat energy completely into work violates:

• A. Zeroth law of thermodynamics
• B. 1st law of thermodynamics
• C. 2nd law of thermodynamics✓
• D. 1st and 2nd law of thermodynamics

Explanation: According to this law,it's impossible for an engine to extract heat from a hot reservoir and convert it completely into useful work. All engines lose some heat to the environment.

Q160. As the temperature of a black body is raised, the black body radiations become richer in:

• A. Intermediate wavelengths
• B. Long wavelengths
• C. Short wavelengths✓
• D. Low frequencies

Explanation: Wein's displacement law states that temperature is inversely related to wavelength. Therefore, increasing temperature results in shorter wavelengths.

Q161. The rapid escape of air from a burst tyre is an example of:

• A. Isothermal
• B. Adiabatic✓
• C. Isobaric
• D. Isochoric

Explanation: Isothermal process is the one where temperature remains constant.Isochoric process is the one where volume remains constant.Isobaric process is the one where pressure remains constant.Adiabatic process is a rapid process where heat excahnge of a system is zero. Hence, sudden bursting of a ture is an example of an adibatic process.

Q162. The temperature coefficient of a normal conductor is negative because:

• A. Resistance increases with an increase in temperature
• B. Resistance decreases with an increase in temperature✓
• C. Resistance decreases with decrease in temperature
• D. Resistance is independent of temperature change

Explanation: A negative coefficient for a material means that its resistance decreases with an increase in temperature. Option B is therefore the correct answer.Note: Semiconductor materials (carbon, silicon, germanium) typically have negative temperature coefficients of resistance.

Q163. The value of absolute zero on the Fahrenheit temperature is:

• A. 359.4
• B. -459.4✓
• C. 100
• D. -259.4

Explanation: Absolute zero, is temperature at which a thermodynamic system has the lowest energy. It corresponds to −273.15 °C on the Celsius temperature scale and to −459.67 °F on the Fahrenheit temperature scale.Absolute zero is the lowest limit of the thermodynamic temperature scale, a state at which the enthalpy and entropy of a cooled ideal gas reach their minimum value, taken as zero kelvin. The fundamental particles of nature have minimum vibrational motion, retaining only quantum mechanical, zero-point energy-induced particle motion. The theoretical temperature is determined by extrapolating the ideal gas law; by international agreement, absolute zero is taken as −273.15 degrees on the Celsius scale (International System of Units)which equals −459.67 degrees on the Fahrenheit scale.

Q164. During each cycle, a heat engine with an efficiency of 25% takes in 800J of energy. How much waste heat energy is expelled in each cycle?

• A. 100J
• B. 200J
• C. 400J
• D. 600J✓

Explanation: If the efficiency of the engine is 25%, then the energy that is output for useful work is 25% of the input energy, which is 25% of 800 J= 200 J. The remaining 800 J – 200 J = 600 J is expelled as waste heat.

Q165. Systems in thermodynamics are separated from their surroundings by:

• A. Pressure
• B. Universe
• C. Boundary✓
• D. Temperature

Explanation: The mass or region outside the system is called the surroundings, and the surface that separates the system and the surroundings is called the boundary.In thermodynamics, a boundary is a conceptual or physical division that separates a system from its surroundings. The system is the specific part of the universe under consideration, and the surroundings include everything else. The boundary defines what is inside the system and what is outside.

Q166. If Cv = 2.5 R, Cp = ?

• A. 0.4 R
• B. 2R/7
• C. 2.5 R
• D. 3.5 R✓

Explanation: R = Cp-CvSo, Cp = R + 2.5 RCp = 3.5 R

Q167. An electric dipole is situated in a non-uniform electric field. It may experience:

• A. A resultant force and a couple✓
• B. Only force
• C. Only couple
• D. Any of the above

Explanation: An electric dipole always experiences a torque when placed in either uniform or non-uniform electric field. But in non-uniform electric field, dipole will also experience net force of attraction. So, the electric dipole in non-uniform electric field experiences both torque and force.

Q168. Two plates are at potentials 20V and -20V respectively with a separation of 2cm between them. The electric field between them is:

• A. 2000 V/m✓
• B. 1000 V/m
• C. 500 V/m
• D. 300 V/m

Explanation: E=V/d(Note: distance should be in meters. So 2cm = 0.02m)20-(-20)/0.02= 2000 V/m

Q169. If a dielectric is placed between two plates of a capacitor, the net capacitance:

• A. Decreases
• B. Increases✓
• C. Remains constant
• D. Becomes zero

Explanation: The dielectric placed between the plates of the capacitor reduces the electric field strength between the plates of the capacitor, this results in a small voltage between the plates for the same charge. The capacitor stores more charge for a smaller value of voltage. Therefore, the capacitance increases.

Q170. Two capacitors C1 (12 F) and C2 (24 F) are connected in series across a 36 V supply. The charge stored on each of them will be:

• A. 288 C, 288 C✓
• B. 4770 C, 4770 C
• C. 5810 C, 6610 C
• D. 7170 C, 8140 C

Explanation: In series, charge remains same. This cancels option C and D.To calculate Total capacitance:1/C = 1/12 + 1/24 C=8FC=Q/V8 x 36= 288COption A is therefore the correct answer.

Q171. In an NPN transistor, the current IE that flows in the emitter circuit is:

• A. IC + IB✓
• B. IC - IB
• C. IC x IB
• D. Zero

Explanation: NPN transistors let the current flow from the emitter to the collector and base controls the flow of current through it. Therefore, IE = IC+IB.

Q172. In photodiodes, the bias voltage is applied in _ bias form.

• A. Forward
• B. Resistance
• C. Reverse✓
• D. Converse

Explanation: A photo diode is made to act in reverse bias form.

Q173. In capacitors, energy is stored in the form of:

• A. Gravitational Potential
• B. Chemical Potential
• C. Electric Intensity✓
• D. Magnetic Induction

Explanation: A capacitor stores energy in form of electrostatic field (or electricfield intensity) between the plates of the capacitor.

Q174. Velocity of sound in air is 332m/s. Velocity of sound in vacuum would be:

• A. More than 332m/s
• B. Less than 332m/s.
• C. 332m/s
• D. Zero✓

Explanation: Sound waves are longitudinal waves and they need a medium to travel. Thus, they cannot travel in vaccum.

Q175. If a wave can be polarized, it means it is a:

• A. Longitudinal wave
• B. Stationary wave
• C. Superimposed wave
• D. Transverse wave✓

Explanation: Fact. Transverse waves are the only waves that can be polarized.

Q176. Astronomers calculate the speed of distant stars moving away from us using:

• A. Beats
• B. Interference
• C. Superposition principle
• D. Doppler effect✓

Explanation: If a star is moving toward us, its light wavelength get shorter, producing a blueshift. If a star is moving away, its light waves get stretched out to longer, redder, wavelengths, producing a redshift. The faster the star, the greater this shift, so observers can measure the line-of-sight speed from the Doppler shift.

Q177. The wavelength associated with electrons is equal to that of:

• A. Visible spectrum
• B. X rays✓
• C. Radio waves
• D. Infrared waves

Explanation: We know that X-rays are produced due to transition of electron from higher shell yo lower shell , producing continuous and characteristic X rays So the photon produced by electron is actually X ray , so wavelength produced is actually associated with X rays.

Q178. How many modulations are possible for a sinusoidal carrier wave?

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

Explanation: Only 3 modulations are possible. Amplitude Modulation, Frequency Modulation and Phase Modulation.

Q179. Select a method which causes the oxidation of chemical constituent of a bacterial cell:

• A. Steam
• B. Dry heat✓
• C. Filtration
• D. Radiation

Explanation: Dry heat helps kill the organisms using the destructive oxidation method. This helps destroy large contaminating bio-molecules such as proteins. The essential cell constituents are destroyed and the organism dies. The temperature is maintained for almost an hour to kill the most difficult of the resistant spores.

Q180. The bacteria can cope in unfavorable condition by producing:

• A. Mesosomes
• B. Zygospores
• C. Endospores✓
• D. Hyphae

Explanation: Numerous strategies exist in bacteria to cope with stressful conditions including the formation of endospores. An endospore is a dormant, tough, non-reproductive structure produced by a small number of bacteria from the Firmicute family. The primary function of most endospores is to ensure the survival of a bacterium through periods of environmental stress.

Q181. Rod-shaped bacteria are known as _

• A. Spirilla
• B. Bacilli✓
• C. Spirochete
• D. Cocci

Explanation: Bacilli are rod shaped bacteria. Cocci are spherical shaped bacteria. Spirillas are corkscrew shaped bacteria. Spirochetes are any group of spiral shaped bacteria.

Q182. In cross-section each centriole consists of nine (each in triplets) of:

• A. Microfilaments
• B. Microvilli
• C. Microtubules✓
• D. Intermediate filaments

Explanation: Typical centrioles are made of 9 triplets of microtubules organized with radial symmetry.

Q183. The finger like infoldings which are formed by inner membrane of mitochondria are called:

• A. Matrix
• B. Porin
• C. Cristae✓
• D. Ribosomes

Explanation: Cristae are folds in the inner mitochondrial membrane.

Q184. Which of the following proteins is present in microtubules?

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

Explanation: Tubulin is the most abundant protein found in microtubules while myosin, actin and tropomyosin are found in microfilaments.

Q185. Which of the following diseases is sexually transmitted?

• A. Tuberculosis
• B. AIDS✓
• C. Dengue Fever
• D. Cholera

Explanation: Acquired immunodeficiency syndrome (AIDS) is a chronic, potentially life-threatening condition caused by the human immunodeficiency virus (HIV). By damaging your immune system, HIV interferes with your body's ability to fight infection and disease. You can get HIV from contact with infected blood, semen, or vaginal fluids. Most people get the virus by having unprotected sex with someone who has HIV. Another common way of getting it is by sharing drug needles with someone who is infected with HIV. Hence, Option B is correct. Tuberculosis is caused by bacteria that spread from person to person through microscopic droplets released into the air. This can happen when someone with the untreated, active form of tuberculosis coughs, speaks, sneezes, spits, laughs, or sings. Hence, Option A is incorrect. When a mosquito bites a person infected with a dengue virus, the virus enters the mosquito. Then, when the infected mosquito bites another person, the virus enters that person's bloodstream and causes an infection. Hence, Option C is incorrect. A person can get cholera by drinking water or eating food contaminated with cholera bacteria. In an epidemic, the source of the contamination is usually the feces of an infected person that contaminates water or food. Hence, Option D is incorrect.

Q186. Leaves of _ are used to cure cough and cold in horses.

• A. Glycyrrhiza glabra✓
• B. Cassia alata
• C. Bamboo
• D. Both bamboo and Glycyrrhiza glabra

Explanation: Glycyrrhiza glabra, commonly known as licorice, is a herbaceous perennial plant native to southern Europe and parts of Asia. The plant is well-known for its sweet-tasting roots, which have been used for centuries for medicinal and culinary purposes. Licorice is known to be soothing for the respiratory system. It is often used to relieve coughs, sore throats, and respiratory discomfort.

Q187. Such inflorescence in which the main axis is elongated and bears sessile flowers is called:

• A. Raceme
• B. Spike✓
• C. Cyme
• D. Panicle

Explanation: The inflorescence in which the main axis is elongated and bears sessile flowers is called a spike. In a spike, the flowers are arranged in an acropetal manner, which means that the lowermost flowers mature first and the upper ones mature later. The flowers are directly attached to the main axis without any pedicels or stalks. A spike can be unbranched or branched, and the flowers can be arranged in various patterns such as dense, loose, or interrupted. Examples of plants with spike inflorescence include wheat, rye, and barley.

Q188. Three of the following statements about enzymes are correct and one is wrong. Which one is wrong?

• A. Enzymes require optimum pH for maximal activity
• B. Enzymes are denatured at high temperatures but in certain exceptional organisms, they are effective even at temperatures such as 80° and­ 90°C
• C. Enzymes are highly specific
• D. Most enzymes are proteins but some are lipids✓

Explanation: Enzymes are mostly proteins but some are RNA (ribozymes). No lipid which works as an enzyme is known.

Q189. Which of the following shows the Planck's quantum theory?

• A. E =hcv
• B. E = c/v
• C. E = hv✓
• D. None of these options are correct

Explanation: In chemistry, Frequency is denoted by vSo, the Planck's quantum theory isE = hv where h is the Planck's constantIt can be rewritten asE = hc/λ since frequency(v) = c/λ where c is the speed and λ is the wavelength.

Q190. If energy of activated complex is close to energy of reactants, it means that the reaction is:

• A. Fast✓
• B. Moderate
• C. Slow
• D. Very slow

Explanation: If energy of activated complex is close to energy of reactant then reaction is fast, spontaneous and endothermic. Activated state is the state when reactants gain sufficient energy to be converted into product hence, if energy of reactants is already close to the energy of activated complex, so they will not take time and energy to get converted to activated state.Thus they will react spontaneously and fast.

Q191. According to the collision theory of bimolecular reactions in gas phase, minimum amount of energy is required for an effective collision is known as:

• A. Heat of reaction
• B. Rate of reaction
• C. Has no effect on the reaction
• D. Energy of activation✓

Explanation: Minimum amount of energy in addition to average kinetic energy is called activation energy or minimum amount of energy which must be possessed by reactant to convert into product is called activation energy. OR Minimum amount of energy required for an effective collision is called activation energy.

Q192. If the temperature of the atmosphere is 30oC then which of the following will havehighest average speed

• A. O2
• B. H2✓
• C. Ne
• D. N2

Q193. Some substances are good conductor of electricity in both the solid and liquid states. These substances are generally

• A. ionic substances
• B. metallic substances✓
• C. molecular solids
• D. covalent network solids

Explanation: Metals are generally good conductors of electricity in both the solid and liquid states. This is because metals have a unique structure where electrons are delocalized and can move freely throughout the material. This "sea of electrons" allows for the conduction of electricity.

Q194. The frequency of second pendulum is:

• A. 1 hertz
• B. 2 hertz
• C. 0.5 hertz✓
• D. None

Explanation: The frequency (f) of a pendulum can be calculated using the formula:f=1/Twhere f is the frequency andT is the time-period.So, f= ½= 0.5hz

Q195. Total pressure on 1 m x 1 m gate immersed vertically at a depth of 2 m below the free water surface will be:

• A. 1000 kg
• B. 2000kg✓
• C. 4000kg
• D. 8000 kg

Explanation: The total pressure on a vertical gate submerged in water can be calculated using the hydrostatic pressure formula:P=ρ⋅g⋅h⋅AThe total pressure is given by the product of pressure and area:Total Pressure=P⋅ATo convert Newtons to kilograms (1 kg = 9.8 N), we divide by 9.8:Total pressure= 19600N/9.8N/kgTotal Pressure≈2000kg

Q196. When a beam of light traveling in a rare medium is reflected from a denser medium it:

• A. Suffers no phase change.
• B. Undergoes a phase change of 1800.✓
• C. Undergoes a phase change of 2700.
• D. Undergoes a phase change of 900.

Explanation: When light traveling in a rare (less dense) medium is reflected from a denser medium, the reflected light undergoes a phase change of 180 degrees. This is due to the change in the refractive index between the two media.

Q197. Two water pipes of diameters 4 cm and 8 cm are connected to a supply line. The velocity of flow of water in the pipe 4 cm diameter is:

• A. ¼ times
• B. 4 times✓
• C. Twice
• D. ½ of 8 cm diameter pipe

Explanation: The velocity of flow of water in a pipe is inversely proportional to the square of its diameter, according to the principle of continuity.Mathematically, the equation is:v1​/v2​=(d22​/d12​)

Q198. The density of water in F.P.S system is

• A. 50lb/ft2
• B. 50ft/lb
• C. 50ft/lb3
• D. 50lb/ft3✓

Explanation: In the F.P.S. (Foot-Pound-Second) system, the density of water is commonly expressed in pounds per cubic foot (lb/ft3).

Q199. A car engine is based on the principle of:

• A. Bernoulli’s equation
• B. Ventura relation
• C. Torricelli’s theorem
• D. None✓

Explanation: The car engine operates based on the principles of thermodynamics and internal combustion, and it is not directly based on Bernoulli's equation, Venturi effect, or Torricelli's theorem. The combustion of fuel and air mixture in the engine cylinders generates power that drives the vehicle. This process involves concepts such as the Otto cycle (for spark-ignition engines) or the Diesel cycle (for compression-ignition engines), which are part of the broader field of thermodynamics.

Q200. In case of streamed lined flow of liquid the loss of energy is:

• A. Maximum
• B. Minimum✓
• C. Infinite
• D. Equal to what is in turbulent flow.

Explanation: In the case of streamlined (laminar) flow of liquid, the loss of energy is typically at a minimum. This is because streamlined flow is characterized by smooth and orderly movement of fluid particles in parallel layers, resulting in lower frictional losses compared to turbulent flow.