Biology

Single correct answer type: 1. Which of the following is not a derivative of cholesterol? (A) Vitamin-B (B) Vitamin-D (C) Bile salts (D) Steroid Solution: (A) Among the given options, vitamin-B is not a derivative of cholesterol. It (cholesterol) is a type of lipid molecule. It is an essential structural component of all animal cell membranes. It also serves as a precursor for the biosynthesis of steroid hormones, bile salts and vitamin-D. 2. Shape of chloroplast of <i>Ulothrix</i> is (A) Star-shaped (B) Band-shaped (C) Girdle-shaped (D) Spinal-shaped Solution: (C) The chloroplast of <i>Ulothrix</i> is girdle-shaped containing one or more pyrenoids. The thallus of <i>Ulothrix</i> is filamentous, long, unbranched and multicellular. It is a freshwater alga growing on substratum like rocks, sand, etc. 3. What is the function of Kupffer's cells? (A) Bile secretion (B) Digestion of lipid (C) Phagocytosis (D) Digestion of protein Solution: (C) The main function of Kupffer's cells is phagocytosis. They are specialized macrophages located in the liver, lining the walls of the sinusoids. Kupffer's cell activation is responsible for early ethanol induced liver injury, common in chronic alcoholics. 4. Which one is an anti-allergic antibody? (A) (B)

(C) (D) Solution: (C) is an anti-allergic antibody. It plays a pivotal role in response to allergens such as anaphylactic drugs, bee stings. etc. They are synthesised by plasma cells. It is found in only mammals. 5. Loss of water from body occurs by all of the following except (A) Muscles (B) Lungs (C) Kidney (D) Skin Solution: (A)

The loss of water from body occurs by lungs, kidney and skin. Muscles do not lose water. Skin loses water in the form of sweat. Kidneys loose water in the form of urine. From lungs, during respiration some water is lost. 6. Pollenkitt is present in (A) Anemophily (B) Entomophily (C) Malacophily (D) Zoophily Solution: (B) Pollenkitt is present in entomophily. It is a sticky covering on the surface of pollen grains. Its major function is to make the pollen to stick to the bugs. Thus, it helps in the pollination. 7. Which motile-stage of protozoans is helpful in feeding? (A) Pseudopodium (B) Cilia (C) Flagella (D) Tentacles Solution: (A) Pseudopodium is helpful in the feeding of protozoans. It is a temporary cytoplasm-filled projection of a eukaryotic cell membrane. It can be used for motility or for ingesting nutrients or other particulate matter. 8. Function of hypothalamus is (A) Thermoregulation (B) Water balance (C) Control of hormone function (D) All of the above Solution: (D) The functions of hypothalamus include thermoregulation, water balance and control of hormone functions. It is located below the thalamus and is a part of limbic system. It synthesises and secretes certain neurohormones which in turn stimulate or inhibit the secretion of pituitary hormones. It controls other activities also like sleep, hunger, body temperature, etc. 9. Inhibin is composed of (A) Glycoprotein (B) Lipoprotein (C) Steroid (D) Amino acid derivative Solution: (A)

lnhibins are dimeric glycoproteins composed of an subunit and either a (inhibin ) or a subunit (inhibin ). They are mainly produced in gonads and provide negative regulation of FSH secretion. 10. What is ribotide?

(A) Ribose Uracil Phosphate (B) Deoxyribose Uracil Phosphate (C) Deoxyribose Thymine Phosphate

(D) Ribose Thymine Phosphate Solution: (A)

Ribotide is a nucleotide containing ribose as its pentose component. It is considered a molecular precursor of nucleic acids. In living organisms, the most common bases for ribotides are adenine,

guanine, cytosine or uracil. Therefore, option ( ) i.e. Ribose Uracil Phosphate is correct. 11. How many molecules of pyruvic acid are formed in glycolysis?

(A)

(B) (C) (D) Solution: (A)

In glycolysis, molecules of pyruvic acid are formed. It is the first step of degradation of glucose. The main purpose of glycolysis is the generation of energy in the form of ATP. However, comparatively more ATPs are formed downstream of glycolysis through the complete oxidation of pyruvate.

12. Molecular formula of chlorophyll is (A)

(B) (C)

(D) Solution: (A) The molecular formula of chlorophyll is . It helps in photosynthesis by absorbing

light energy. It is more soluble in polar solvents than chlorophyll because of its carbonyl group. It is of yellow colour and primarily absorbs blue light. 13. Non-essential amino acid is (A) Valine (B) Arginine (C) Histidine (D) Lysine Solution: (B) Among the given options, arginine is a non-essential amino acid. Such amino acids can be made within the body and so are not essential to the human diet. Valine, histidine and lysine are essential amino acids. 14. Non-disjunction in meiosis results in (A) Trisomy (B) Normal diploid (C) Gene mutation (D) None of these Solution: (A) Non-disjunction in meiosis results in trisomy, i.e. the presence of an extra chromosome. Such

individuals have chromosomes instead of . Some examples of such abnormalities include

Down's syndrome ( trisomy). Patau's syndrome ( trisomy) and Edward's syndrome ( trisomy). 15. Caryopsis is present in (A) Wheat (B) Groundnut (C) Coconut

(D) Mango Solution: (A) Caryopsis is present in wheat. It is a type of simple dry fruit. It is also called as grain. In such fruits the ovary wall and seed coat fuse making it difficult to separate the two. 16. AB blood group shows (A) Codominance (B) Incomplete dominance (C) Polygenic inheritance (D) Pleiotropy Solution: (A)

In humans, AB blood group shows codominance. Here, allele for type blood is codominant with

allele for type blood. In heterozygotes, expresses the characteristics of both and

antigens, i.e. possess RBCs that carry both and antigens at their surface. 17. What is the symmetry of medusa? (A) Bilateral (B) Radial (C) Asymmetrical (D) Biradial Solution: (B) The medusa of <i>Obelia</i> shows radial symmetry. It is a free-swimming, umbrella-like sexual

generation. It is formed by blastostyle. It brings about sexual reproduction and dispersal of species.

18. Which one is a parasitic alga? (A) <i>Oedogonium</i> (B) <i>Cephaleuros</i> (C) <i>Spirogyra</i> (D) <i>Cladophora</i> Solution: (B) <i>Cephaleuros</i> is a parasitic thalloid green alga. Its common name is red rust. This alga is parasitic on some important economic plants of the tropics and subtropics, e.g. tea, guava, mango, coffee, etc. It damages the area of algal growth on leaves or kills the new shoots or disfigure fruit.

19. of malic acid is (A) (B)

(C) (D) Solution: (C)

of malic acid is . Respiratory Quotient ( ) is the ratio of the volume of produced to the volume of consumed in respiration over a period of time. is slightly more than unity when organic acids are broken down as respiratory substrates under aerobic conditions, e.g. malic acid. li i

20. Which one is present in the urine of pregnant woman?

(A) (B) (C) Oestrogen (D) FSH Solution: (A)

(Human Chorionic Gonadotropin) is present in the urine of pregnant woman. It is secreted by placenta. It stimulates the corpus luteum that continues to secrete progesterone. 21.

Above diagram represents (A) Anaphase-I (B) Metaphase-I (C) Telophase-I (D) Prophase-I Solution: (A)

The given figure is showing anaphase of meiosis. It begins when the two chromosomes of each bivalent separate and start moving towards opposite poles of the cell. Unlike the anaphase of mitosis, the sister chromatids remain attached at their centromeres and move together toward the poles. 22. Histamine is secreted by (A) Mast cells (B) Kupffer’s ells (C) Oxyntic cells (D) Neutrophils Solution: (A) Histamine is secreted by mast cells. It is an organic nitrogenous compound involved in local immune responses. It is responsible for inflammatory responses. It increases the permeability of the capillaries to white blood cells and some proteins to allow them to engage pathogens in the infected tissues. 23. Peyer’s p t hes re present in (A) Ileum (B) Jejunum (C) Duodenum (D) Sacculus rotandus

Solution: (A) Peyer’s p t hes re present in ileum. They re org nise lymphoi folli les. They form n import nt part of the immune system by monitoring intestinal bacteria populations. They prevent the growth of pathogenic bacteria in the intestine. 24. The correct sequence is

(A) Zygote Cleavage Morula Blastula Gastrula (B) Cleavage Zygote Morula Blastula Gastrula

(C) Zygote Morula Blastula Cleavage Gastrula (D) Zygote Blastula Morula Cleavage Gastrula Solution: (A)

The correct sequence is Zygote Cleavage Morula Blastula Gastrula.

At about hrs after fertilisation. the zygote divides into smaller cells by a process called cleavage. It is division of cells. It results in a solid ball of cells, called morula. It Is a celled stage. It forms blastula which Is a celled stage. It contains a fluid-filled cavity called blastocoel. It ultimately leads to gastrula stage. It is a multilayered structure which is followed by organogenesis. 25. Purkinje’s fibres re foun in (A) Heart (B) Liver (C) Brain (D) Lungs Solution: (A) Purkinje’s fibres re foun in he rt. These re the part of impulse conducting network of the heart. They rapidly transmit impulses from the atrioventricular node to the ventricles. 26. Gene transfer is present in (A) Biolistics (B) Hybridisation (C) Tissue culture (D) Vegetative propagation Solution: (A) Gene transfer is present in biolistics. This technique involves firing of microscopic gold particles coated with the foreign DNA at the cells using a compressed air gun. It is designed to overcome the problem of strong cell wall in plant tissues. These particles can penetrate the cell wall, the cell and the nuclear membrane to deliver the DNA to the nucleus. 27. Which one is used in tissue culture? (A) Explant (B) Somaclones (C) Hybridisation (D) None of these Solution: (A) Explant is used in plant tissue culture. It is an excised plant part which has the potential to give rise to whole new plant. The plants obtained through this technique are morphologically and genetically similar to each other and to their parent plant. 28. What is common between a eukaryotic and prokaryotic flagella? (A) Same structure (B) Both are used for locomotion

(C) Composed of same proteins (D) Both are extension of cell membrane Solution: (B) The common feature between eukaryotic and prokaryotic flagella is that both are used for locomotion.

Prokaryotic flagellum is single stranded while eukaryotic flagellum is stranded. EukaryotIc flagellum has two parts, basal body and shaft, while prokaryotic flagellum consists of three parts, basal body, hook and filament. Prokaryotic and eukaryotic flagellum are made up of flagellin and tubulin proteins, respectively. 29. Heterotrichous thallus is shown by which organism? (A) <i>Chlamydomonas</i> (B) <i>Ectocarpus</i> (C) <i>Spirogyra</i> (D) <i>Volvox<i/> Solution: (B) The heterotrichous thallus is shown by <i>Ectocarpus</i>. It is a filamentous marine brown alga which has both upright and prostrate regions. Such a growth is called heterotrichous.

30. What is acrosomal reaction? (A) Contact of sperms with eggs (B) Digestion of zona pellucida (C) Disintegration of acrosome (D) Contact of acrosome and nucleus of egg Solution: (B) Acrosomal reaction is digestion of mina pellucida. This involves the progressive fusion of the acrosomal membrane with the plasma membrane of the sperm. It creates pores through which the acrosomal enzymes can be released by exocytosis. These enzymes include a protein digesting enzyme, corona penetrating enzyme, zona lysin (acrosin) and hyaluronidase. These enzymes allow the sperm to digest a path through the zona pellucida to the oocyte. 31. Daily requirement of vitamin-A for adult women is

(A) micrograms

(B) micrograms (C) micrograms (D) micrograms Solution: (B)

The recommended daily amount of vitamin-A for adult women is micrograms. Vitamin-A is a nutrient important for good vision, growth, cell division, reproduction and immunity. It is found in spinach, dairy products, etc.

32. Which of these is incorrect for plants? (A) Kranz anatomy

(B) acceptor is

(C) Case in mesophyll (D) RuBisCO in mesophyll Solution: (D)

Among the given options, option ( ) is incorrect about plants. The mesophyll cells of plants do not possess RuBisCO enzyme. plants show Kranz anatomy. In these plants, the initial fixation

of occurs in mesophyll cells. The primary acceptor of is Phosphoenol Pyruvate or PEP. It combines with in the presence of PEP carboxylase or PEPCase to form oxaloacetic acid or oxaloacetate.

33. Rouleaux formation is related to which of the ⁄ ? (A) RBCs (B) WBCs (C) Platelets (D) Monocytes Solution: (A) Rouleaux formation is related to RBCs. In resting and slow flowing blood, the RBCs aggregate to form rouleaux, i.e. they are piled up on the top of each other. Fibrinogen favours rouleaux formation. 34. Which of the following is not a plant growth inhibitor? (A) Dormin (B) IAA (C) Ethylene (D) ABA Solution: (B) IAA is a plant growth promoter while dormin, abscisic acid and ethylene are plant growth inhibitors. IAA (Indole Acetic Acid) is an auxin. It was discovered by Koge et al. (1934). Auxins are synthesised in shoot apices, leaf primordia and developing seeds from amino acid, tryptophan. 35. What is the RQ of glucose? (A) One (B) Less than one (C) More than one (D) Infinite Solution: (A)

The RQ (Respiratory Quotient) of glucose is 1 RQ is the ratio of the volume of produced to the volume of oxygen consumed in respiration over a period of time.

36. Brunner’s gl n is lo te in (A) Duodenum (B) Jejunum (C) Ileum (D) Stomach Solution: (A)

The Brunner's glands are located in duodenum only. They secrete a little enzyme and mucus. The mucus protects the duodenal wall from getting digested. The Brunner's glands open into the crypts of Lieberkuhn. 37. Perianth is found in which family? (A) Cruciferae (B) Solanaceae (C) Liliaceae (D) Malvaceae Solution: (C) Perianth is found in Liliaceae family when there is no distinction of sepals and petals. The individual parts of the perianth are known as tepals, e.g. onion, lily. etc. 38. Which trait is shown by given pedigree analysis?

(A) Autosomal dominant (B) X-Linked dominant (C) Autosomal recessive (D) X-Linked recessive Solution: (A) The given pedigree analysis is showing autosomal dominant trait. If such a trait is present in pedigree, it seldom skips a generation. An autosomal recessive trait may skip a generation. A sex-linked dominant trait is more common in females while a sex-linked recessive trait is more common in males. 39. Which of the following is involved in passive immunity?

(A) IgA (B) IgE (C) IgM (D) IgD Solution: (A) IgA antibody is involved in passive immunity. This type of immunity is produced by a donor other than the infected person or an animal. It is short lived. Human colostrum (Mother's first milk) is rich in IgA antibodies. It provides natural passive immunity to the infant till the age of three months. 40. Fimbriae are associated with which organ? (A) Fallopian tube (B) Uterus (C) Vagina (D) Ovary Solution: (A)

Fimbriae are associated with Fallopian tubes. Each Fallopian tube is about cm long and consists of four parts viz., infundibulum, ampulla, isthmus and the uterine part. Fimbriae are finger-like projections found on the ends of infundibulum. They help in the collection of ovum after ovulation. 41. Linker-DNA is attached to

(A)

(B) (C)

(D) Solution: (A)

Linker-DNA is attached to histone length. Linker DNA connects two adjacent nucleosomes. Its

length is varied (about with ). Nucleosome and linker DNA together constitute chromatosome. Chromatosome contains a histone octamer and DNA.

42. To which of the following, repressor protein is attached? (A) Operator (B) Inducer (C) Promoter (D) Structural gene Solution: (A) Repressor protein is attached to operator gene. It is a regulatory protein synthesised by regulator gene. Repressor is meant for blocking the operator gene so that the structural genes are unable to form mRNAs. 43. Palmella stage is present in (A) <i>Aspergillus</i> (B) <i>Cystopus</i> (C) <i>Chlamydomonas</i> (D) None of these Solution: (C) Palmella stage is present in <i>Chlamydomonas</i>. In adverse conditions, the daughter protoplasts formed by division, do not develop neuromotor apparatus and become motile. However, the parent cell wall gelatinises and forms a matrix around the daughter protoplasts. All cells of palmella stage develop flagella and become motile. They escape from the gelatinous matrix on the arrival of favourable conditions. 44. Formation of corpus luteum is induced by (A) LH (B) Oestrogen (C) FSH (D) Progesterone Solution: (A) The formation of corpus luteum is induced by LH (Luteinising Hormone). The LH causes ovulation and remaining cells of the ovarian follicle develop corpus luteum. It secretes large amount of progesterone which is essential for the maintenance of uterine endometrium.

45. Cell wall of fungi is composed of (A) Chitin (B) Pectin (C) Cellulose (D) Mannans Solution: (A) The cell wall of fungi is composed of chitin. It is the second most abundant carbohydrate. It is a

homopolymer of N-Acetyl Glucosamine (NAG) joined with linkages. NAG is a modification of glucose molecule. 46. Which of the following mRNA can be transcripted as (A) AUG.UGA.UUU (B) UAA.UAV.UGG (C) UAG.UGA.UUV (D) UGA.UUV.UGG Solution: (A) Among the given options, only first one can be transcripted because it possesses an initiation codon-AUG which codes for methionine. Rest of the mRNA sequences start with termination codons, i.e. UAA (Ochre), UAG (Amber) and UGA (Opal). Therefore, these cannot be transcripted. 47. Which is incorrect with reference to chloroplast? (A) Presence of algae and plants

(B) Releases (C) Occurs only in cells with aerobic respiration (D) None of the above Solution: (C) Option ( ) is incorrect about chloroplasts. They are spherical, ovoid or disc-shaped cell organelles. These are found in plants and algae. They are involved in photosynthesis due to the presence of

chlorophyll in them. During photosynthesis, is released. They are not associated with any type of respiration, i.e. aerobic and anaerobic and can be found in any type of cell. 48. Proteins are needed in diet because (A) All amino acids are not available in body (B) During fasting, body utilizes proteins (C) Proteins act as building blocks of our body (D) All of the above Solution: (D) Proteins are polymers of amino acids. These are divided into two categories: essential and non-essential amino acids. Essential amino acids cannot be synthesised in the body and therefore must be included in the diet. Proteins are used as structural components of tissues as channels, transporters, regulatory molecules and enzymes. Proteins can also be utilised as energy sources. Normally, this is a secondary function and becomes important only when there is not enough carbohydrate and fat in the body, e.g. during fasting. 49. Which of the following pituitary hormones works indirectly? (A) MSH (B) TSH (C) GH (D) Oxytocin

Solution: (B) Among the given hormones. TSH (Thyroid Stimulating Hormone) secreted by anterior lobe of pituitary gland, works indirectly. This hormone controls the growth and activity of thyroid gland. It influences the uptake of iodine, the synthesis of the hormones; thyroxine and tri-iodothyronine by the thyroid gland. Rest of the hormones, i.e. MSH (Melanocyte Stimulating Hormone). GH (Growth Hormone) and oxytocin work directly on their target organ. They do not stimulate any other gland.

50. XYY composition (A) Super female (B) Hermaphrodite (C) Male (D) Super male Solution: (D) The individuals having XYY chromosomes are known as super males. They have an additional Y chromosome. They suffer from poly Y male syndrome. These individuals are characterised by abnormal height, mental retardation, antisocial and criminal bent of mind. 51. Which is present at end of eukaryotic mRNA? (A) Poly-A tail

(B) Modified C at (C) (D) Poly-C Solution: (C) At the end of eukaryotic mRNA, mG ( methyl guanosine) is present. In eukaryotes, primary transcript is often larger than the functional RNAs. Therefore, post-transcription processing is required to convert primary transcript of all types of RNAs into functional RNAs. It is of four types; cleavage, splicing, terminal additional and nucleotide modification. The terminal additions include capping and tailing. In capping, is added to end of mRNA. In tailing, polyadenylation occurs which is addition of poly ( ) tail to end of mRNA. 52. Conditions required for cyclic photophosphorylation are (A) Aerobic condition, low light intensity (B) Aerobic condition, optimum light intensity (C) Anaerobic condition, low light intensity (D) Anaerobic condition, optimum light intensity Solution: (B) The conditions required for cyclic photophosphorylation are aerobic condition and optimum light intensity. It is a process of photophosphorylation in which an electron expelled by the excited photocenter is returned. This electron passes through a series of electron carriers. Cyclic photophosphorylation is performed by photosystem-I only.

53. What ⁄ the function (s) of calcium? (A) Blood clotting (B) Muscular contraction (C) Nerve conduction (D) All of these Solution: (D)

Calcium performs all the given functions, i.e. blood clotting, muscular contraction and nerve

conduction. ions are helpful in the formation of pro-thrombinase which catalyses breakdown of prothrombin into thrombin and small peptide fragments. Thrombin is important for the clotting of blood. Calcium plays a key regulatory role in muscle contraction. It helps in exposing the active sites on the F-actin molecules for myosin cross-bridges. Calcium ions help in the transmission of nerve impulse at a chemical synapse. 54. What is the role of sterol in cell membrane? (A) Stability (B) Communication with other cells (C) Secretion (D) Transport Solution: (A)

The role of sterol in cell membrane is to provide stability. Steroles are steroids with carbon long aliphatic side chain at carbon and at least one alcoholic hydroxyl. Cholesterol ( ) is a common sterol found in many animal cell membranes. 55. Where is sacculus rotandus located? (A) Between duodenum and jejunum (B) Between ileum and caecum (C) Caecum and colon (D) Colon and rectum Solution: (B) Sacculus rotundus is located between ileum and caecum. The junction of ileum and large intestine is seen in the form of an orifice called ileocolic or ostium ileocaecal valve. This portion is well-developed in rabbit in the form of swollen portion called sacculus rotandus. 56.

Above diagram represents (A) Metaphase-I (B) Anaphase-I (C) Metaphase-II (D) Anaphase-II Solution: (A) The given diagram represents metaphase-I of meiosis. This stage is more or less similar to metaphase stage of mitosis. The only difference is appearance of paired chromosomes at metaphasic plate.

57. Omega fatty acid is present in (A) Sunflower oil (B) Flax seed oil (C) Groundnut oil (D) Butter Solution: (B)

Omega fatty acid is present in flax seed oil. These are Polyunsaturated Fatty Acids (PUFAs). They are important for normal metabolism. Mammals are unable to synthesise omega fatty acids.

58. Which is the st amino acid? (A) Pyrrolysine (B) Selenocysteine (C) Cystine (D) Histidine Solution: (B)

Selenocysteine (Sec) is the st amino acid in the genetic code. This amino acid contains selenium.

59. What is incorrect about inhibin? (A) It is a lipoprotein (B) Decreases FSH secretion

(C) Molecular weight is between Dalton (D) Secreted by Sertoli cells Solution: (A)

Statement ( ) is incorrect about inhibin. It is a glycoprotein, not lipoprotein. In females, it is secreted by the corpus luteum while in males it is secreted by Sertoli cells. Inhibin inhibits FSH production from

the anterior lobe of pituitary gland. Its molecular weight is Dalton. 60. Eyespot is seen in (A) <i>Chlamydomonas<i/> (B) <i>Ulothrix</i> (C) <i>Spirogyra</i> (D) <i>Polysiphonia</i> Solution: (A) Eyespot is seen in <i>Chlamydomonas</i>. It is a microscopic, eukaryotic, unicellular, pyriform, biflagellate alga. The alga possesses a cup-shaped chloroplast with a red eyespot or stigma and a pyrenoid for storing starch.