MH SET 2021 Life Science Previous year Question Paper Solved
LIFE SCIENCE – MAHARASTRA SET – 2021 Solved Questions Paper with Answers:
1. Sodium Dodecyl Sulphate (SDS) is used while separating proteins by polyacrylamide gel electrophoresis because:
(A) It helps in the solubilization of proteins making it easier to separate
(B) It binds to proteins and confers a uniform negative charge density thereby making them move during electrophoresis
(C) Decreases surface tension of the buffer used for electrophoresis
(D) Stabilizes the protein
Answer: B
2. Cytochalasin D inhibits the formation of microfilaments. Which of the following biological activities will not be hindered?
(A) Muscle contraction
(B) Cytosolic transport of vesicles
(C) Amoeboid movement of phagocytic cells
(D) Formation of cleavage furrow following telophase of mitosis
Answer: B
3. Which of the following statements for “Genetic drift’ is FALSE?
(A) Genetic drift can cause allele frequencies to change at random
(B) Genetic drift can lead to a richness of genetic variation within populations
(C) Genetic drift can cause harmful alleles to become fixed
(D) Genetic drift affects allele frequencies more stronger in small populations
Answer: B
4. According to Oparin, which of the following was not present in the primitive atmosphere of the earth?
(A) methane
(B) hydrogen
(C) water
(D) oxygen
Answer: D
5. Life is said to have originated as coacervates that were formed by:
(A) DNA
(B) Radiations
(C) Polymerization and aggregation
(D) Heat
Answer: C
6. When a taxon is restricted to a particular geographical region, then it is called:
(A) Endemic
(B) Low risk
(C) Threatened
(D) Critically endangered
Answer: A
7. Severe combined immunodeficiency (SCID) mice do not have:
(A) B & T cells
(B) Eosinophils
(C) Basophils
(D) Neutrophils
Answer: A
8. The lichen Roccella is source of:
(A) Condiment
(B) Dye
(C) Antibiotic
(D) Therapeutic compounds
Answer: B
9. Seasonal activity of the cambium leads to:
(A) Ring porous wood
(B) Both ring-porous and diffuse-porous wood
(C) diffuse porous wood
(D) Heteroporous wood
Answer: A
10. Cytoplasmic male sterility occurs as a result of the interaction of:
(A) Nucleus and plastid
(B) Mitochondria and plastid
(C) Nucleus and Golgi
(D) Nucleus and mitochondria
Answer: D
11. The enzyme acetyl CoA carboxylase belongs to which class of enzyme?
(A) Transferases
(B) Hydrolases
(C) Lyses
(D) Ligases
Answer: D
12. According to Vavilov, mango, Nobel canes, rice, and brinjal are some of the crop plants that originate in:
(A) Hindustan centre
(B) Abyssinian centre
(C) Asia minor centre
(D) China centre
Answer: A
13. Which technique is best for determining the precise location of the radioactive isotope in a specimen?
(A) Ultracentrifugation
(B) Atomic force microscope
(C) Autoradiography
(D) Fluorescence microscope
Answer: C
14. In the bacterial glucose phospho-transferase system, glucose is converted to glucose 6-phosphate. What is the source of phosphate?
(A) ATP
(B) Inorganic phosphate
(C) Phosphoenol pyruvate
(D) Creatine phosphate
Answer: C
15. The end product of adenosine monophosphate(AMP) and guanosine monophosphate (GMP) catabolism in normal humans are:
(A) Urea
(B) Creatinine
(C) Xanthine
(D) Uric acid
Answer: D
16. Which of the following protein bonds have a partial double bond character?
(A) Cα − C
(B) Cα − Cβ
(C) Cα − N
(D) C − N
Answer: D
17. When bacteria growing at 20°C are transferred to 40°C, they are most likely to synthesize membrane lipids with more:
(A) Short-chain saturated fatty acids
(B) Long-chain saturated fatty acids
(C) Short-chain unsaturated fatty acids
(D) Long-chain unsaturated fatty acids
Answer: B
18. The type of microscopy we would use to examine bacteria that are stained by gram staining procedure is:
(A) Bright field microscope
(B) Fluorescence microscopy
(C) Dark field microscopy
(D) Transmission electron microscopy
Answer: A
19. Mesenteries are found in:
(A) Diploblastic animals
(B) Triploblastic animals
(C) Friploblastic animals
(D) Pseudocoelomates
Answer: B
20. In a DNA sequence, if nucleotide A is replaced by nucleotide G, the resulting mutation will be a mutation.
(A) Transversion
(B) Frameshift
(C) Missense
(D) Transition
Answer: D
21. Which one of the following is correct for Na − K ATPase?
(A) Na+ and K+bind on the extracellular side, while ATP and ouabain bind on the intracellular side
(B) Na+ and K+ bind on the intracellular side, while ATP and ouabain bind on the extracellular side
(C) K+ and ATP bind on the intracellular side, while Na+ and ouabain bind on the extracellular side
(D) Na+ and ATP bind on the intracellular side, while K+ and ouabain bind on the extracellular side
Answer: D
22. The sequencing of ……. helped investigators conclude that all living things can be classified into three domains
(A) DNA
(B) Cytochrome C
(C) rRNA
(D) Haemoglobin
Answer: C
23. Mark the correct statement:
(A) In active transport molecules move from higher to lower concentration
(B) Carrier protein is involved in both active transport and facilitated diffusion
(C) Energy is consumed to move molecules against the concentration gradient in active transport only
(D) In active transport, only water molecules are transported consuming energy
Answer: B
24. Hybrid zone is a region where:
(A) Hybrids can develop
(B) Genetically distinct populations meet and interbreed to some extent
(C) Genetically similar populations meet but cannot interbreed
(D) Populations of the same geographic region meet and exchange genes
Answer: B
25. The sedimentation coefficient increases with the following:
(A) Increase in solvent density
(B) Increase in friction
(C) Decrease in the mass of the particle
(D) Decrease in a partial specific volume
Answer: D
26. Peptide antigens assemble with class I MHC, aided by:
(A) Chaperone molecules
(B) Immunoglobulins
(C) T cell receptor
(D) Cytokines
Answer: A
27. Type II glycogen storage disease i.e. Pompe disease is a genetic disorder in which the defective enzyme is :
(A) α − 1, 4 → α − 1, 6 branching enzyme
(B) α − 1, 6 Glucosidase
(C) α − 1, 4 Glucosidase
(D) Phosphorylase Kinase
Answer: C
28. Which one of the following is an example of an autoimmune disease?
(A) Parkinson’s
(B) Alzheimer’s
(C) Spasticity
(D) Myesthenia Gravis
Answer: D
29. Which of the following statements about LEAFY (LFY), a regulatory gene in Arabidopsis thaliana is correct?
(A) LFY is involved in floral meristem identity
(B) LFY is involved in leaf expansion
(C) LFY is involved in root meristem identity
(D) LFY is involved in shoot differentiation
Answer: A
30. Binomial nomenclature includes the name of the plant in two words that designate…………
(A) Family and generic name
(B) Generic name and species name
(C) Generic name and specific epithet
(D) Species name and varietal epithet
Answer: C
31. The causal organism for rice blast disease is …….
(A) Xanthomonas oryzae
(B) Magnaparthe grisea
(C) Rhizoctonia solani
(D) Helminthosporium oryzae
Answer: B
32. The center of origin of the Potato is:
(A) India
(B) Brazil
(C) Australia
(D) Peru
Answer: D
33. Helicobacter pylori uses urease to counteract a chemical defense in the human organ in which it lives. This chemical defense is:
(A) Lysozyme
(B) Hydrochloric acid
(C) Superoxide radicals
(D) Sebum
Answer: B
34. Which of the following pair of sugars is of non-reducing nature?
(A) Glucose and galactose
(B) Sucrose and trehalose
(C) Trehalose and glucose
(D) Sucrose and heptulose
Answer: B
35. The enzyme involved in the following reaction is ……
Amino acid + ATP + tRNA ⇌ aminoacyl RNA + AMP + PPI
(A) Aminoacyl tRNA transferase
(B) Aminoacyl tRNA synthetase
(C) Peptidyl transferase
(D) RNA polymerase
Answer: B
36. The resting membrane potential is determined by:
(A) The K+ gradient
(B) The Na+ gradient
(C) The Ca2+ gradient
(D) The Cl− gradient
Answer: A
37. When a robin eats an earthworm, the following happens?
(A) Detrital food webs contribute energy to grazing food webs
(B) Grazing food webs can contribute energy to detrital food webs
(C) Transition of energy from primary producers to primary consumers occurs
(D) Transition of energy from primary consumers to secondary consumers takes place
Answer: A
38. Which of the following is known as the sedimentary cycle because its reservoir is a sedimentary rock?
(A) Carbon cycle
(B) Hydrological cycle
(C) Nitrogen cycle
(D) Phosphorus cycle
Answer: D
39. Which of the following proteins binds to calcium during excitation-contraction coupling?
(A) Tropomyosin
(B) Actin
(C) Myosin
(D) Troponin
Answer: D
40. Both the substrates A and B must be present at the enzyme active site simultaneously is a characteristic feature of …….
(A) All are substrate reactions
(B) Double displacement reactions
(C) Single displacement reactions
(D) Both (B) and (C)
Answer: C
41. Number of nuclear pores depend on the …….
(A) Surface volume of the nuclear membrane
(B) Transcription activity of the cell
(C) DNA content of the cell
(D) Size of the nucleus
Answer: B
42. How many different linear tripeptides can be made from three different L − α neutral amino acids, using each amino acid only once in the chain?
(A) 3
(B) 6
(C) 12
(D) 27
Answer: B
43. The characteristics of organisms involved in symbiotic relationships have developed
(A) by chance
(B) Through co-evolution
(C) by character displacement
(D) Through resource partitioning
Answer: B
44. M-STrIPES is associated with one of the following:
(A) Captive breeding of wild fauna
(B) Indigenous satellite navigation system
(C) Security of national highways
(D) Maintenance of tigers
Answer: D
45. Which of the following is not a method of enzyme immobilization?
(A) Entrapment
(B) Adsorption
(C) Absorption
(D) Cross-linking
Answer: C
46. As part of the circadian clock, the transfer of phosphate groups from adenosine triphosphate (ATP) to PER is required. This is achieved by one of the following:
(A) Caesin kinase 1
(B) Caesin kinase 2
(C) Tyrosine kinase 1
(D) Tyrosine kinase 2
Answer: A
47. In lake succession, the stages are observed in the following order :
(A) Oligotrophic-Mesotrophic Eutrophic
(B) Oligotrophic-Eutrophic-Mesotrophic
(C) Mesotrophic-Oligotrophic-Eutrophic
(D) Eutrophic-Mesotrophic-Oligotrophic
Answer: A
48. The carrying capacity of a population is determined by its :
(A) Gross primary production
(B) Net energy
(C) Net production
(D) Gross usage
Answer: C
49. Chlorophyll-b is distinguished from chlorophyll-a by having a …………. Group in place of a ………… group.
(A) Acetyl, formyl
(B) Methyl, formyl
(C) Formyl, methyl
(D) Formyl, acetone
Answer: C
50. The proteins that are sorted to the mitochondrial matrix are………….. in nature.
(A) hydrophobic
(B) hydrophilic
(C) amphipathic
(D) amphoteric
Answer: C
51. Normal RBCs are:
(A) Biconcave in humans and in frogs
(B) Nucleated in camels and enucleated in humans
(C) Biconcave in camels and in frogs
(D) Enucleated in humans and in camels
Answer: B
52. Which one of the following pairs executes their functions by binding with cytoplasmic receptors?
(A) Estrogen and noradrenaline
(B) Growth hormone and progesterone
(C) Growth hormone and GABA
(D) Estrogen and progesterone
Answer: D
53. Artificial ripening of bananas can be induced by :
(A) Auxin
(B) Cytokinin
(C) Ethylene
(D) Polyamines
Answer: C
54. Diplospory and parthenogenesis lead to the development of :
(A) Haploid embryo
(B) Diploid embryo
(C) Viviparous embryo
(D) Adventive embryo
Answer: D
55. Which one of the following is a correct combination for Kala-azar disease?
(A) Sandfly and Leishmania
(B) Glossina fly and Trypanosoma
(C) Mosquito and Plasmodium
(D) Mosquito and Micro-filarial Worm
Answer: A
56. Match the following and choose the correct combination :
(a) Sulphur (1) Chlorophyll
(b) Zinc (2) Nitrogenase
(c) Magnesium (3) Methionine
(d) Molybdenum (4) Auxin
(A) a − 1, b − 2, с − 3, d − 4
(B) a − 3, b − 4, c − 1, d − 2
(C) a − 3, b − 1, c − 2, d − 4
(D) a − 2, c − 4, c − 1, d − 3
Answer: B
57. ………… are the simplest transposable element that contains inverted repeat sequences at each end and a gene
encoding transposase.
(A) Composite transposon
(B) Insertion element
(C) Virus
(D) Prion
Answer: B
58. The common feature of the following bacteriophages φ × 174, OB, N4, and P1 is :
(A) Single-stranded DNA genome
(B) RNA genome
(C) Circular genome
(D) All infect E. coli
Answer: D
59. Protein synthesis in eukaryotes is inhibited by :
(A) Chloramphenicol
(B) Streptomycin
(C) Cephalosporin C
(D) Cycloheximide
Answer: D
60. With reference to plants, gynogenesis refers to :
(A) Initiation of gynoecium
(B) Development of gynoecium
(C) Development of haploid plants from the egg cell of unfertilized female gametophyte in vitro
(D) Development of an ovary
Answer: C
61. A linear DNA is 100% labeled at one end and has 3 restriction sites for EcoRI. If it is digested by EcoRI so that possible fragments are produced, how many of these fragments will be labeled, and how many non-labeled?
(A) 4 labeled and 6 unlabelled
(B) 6 labeled and 4 unlabelled
(C) 3 labeled and 5 unlabelled
(D) 3 labeled and 3 unlabelled
Answer: A
62. Inclusive fitness is a measure of:
(A) The selective advantage of group fitness
(B) The reproductive fitness of an organism and its relatives
(C) The selective advantage of the assortative selection
(D) The selective advantage of stabilizing selections
Answer: B
63. NMR is a very important technique for the determination of biopolymer structure. NMR experiments are not limited to the study of protons only. Which of the following represents a correct group of isotopes used to obtain resonance signals?
(A) 1H, 12C, 15N, 19F
(B) 1H, 13C, 14N, 19F
(C) 1H, 12C, 14N, 19F
(D) 1H, 13C, 15N, 19F
Answer: D
64. Cryopreservation is a process of :
(A) ex-situ in vitro conservation
(B) ex situ ex vitro conservation
(C) in situ in vitro conservation
(D) in situ ex vitro conservation
Answer: A
65. Which of the following does not need an insect vector for transmission?
(A) Rickettsia prowazekii
(B) Rickettsia rickettsi
(C) Ehrlichia chaffeensis
(D) Coxiella burnetti
Answer: D
66. Hepadnaviruses (e.g. Hepatitis B virus) differ from other DNA viruses as their genome replication involves :
(A) DNA-dependent DNA polymerase
(B) Reverse transcriptase
(C) RNase H
(D) RNA-dependent RNA polymerase
Answer: B
67. In the fermentor, the top portion left without broth is called :
(A) Shaft
(B) Headspace
(C) Impeller
(D) Sparger
Answer: B
68. Which of the following organisms get energy only by fermentative metabolism?
(A) Lactobacillus bulgaricus
(B) Bacillus subtilis
(C) E. coli
(D) Pseudomonas putida
Answer: B
69. In the fertilized egg, cortical granule reaction required for slow block polyspermy, is initiated by :
(A) Na+
(B) Mg2+
(C) K+
(D) Ca2+
Answer: D
70. When the velocity of enzyme activity is plotted against substrate concentration, which of the following is obtained?
(A) Hyperbolic curve
(B) Parabola
(C) Straight line with positive slope
(D) Straight line with negative slope
Answer: A
71. Anticancer drug, cyclophosphamide, is metabolized in the body by glutathionation reaction. What is the type of this reaction?
(A) Reduction
(B) Glucuronidation
(C) Conjugation
(D) Oxidation
Answer: D
72. In non-competitive inhibition,
(A) Inhibitor binds to the active site of the enzyme
(B) Inhibitor binds at a site other than active site and may bind to either E or ES complex
(C) Inhibitor binds to a site other than the active site and binds only to the ES complex
(D) Inhibitor binds at a site other than active site and binds only to E
Answer: B
73. Mangrove swamps are found along ……………
(A) Tropical and subtropical coast-lines
(B) Rocky coastlines
(C) Temperate coastlines
(D) Arctic coastlines
Answer: A
74. Indicate the ionic species that predominates at pH 4, 8, and 11 for ammonia :
(A) NH4+ at pH 4,NH4+ at pH 8 and NH3 at pH 11
(B) NH4+ at pH 4,NH3 at pH 8 and NH4+ at pH 11
(C) NH3 at pH 4,NH4+ at pH 8 and NH4+ at pH 11
(D) NH3 at pH 4,NH4+ at pH 8 and NH3 at pH 11
Answer: A
75. Which of the following transcription factor act as a positioning factor for RNA polymerase II and binds to the promoter?
(A) TF II B
(B) TF II C
(C) TF II D
(D) TF II E
Answer: C
76. Ti plasmid used in genetic engineering is obtained from:
(A) Bacillus thuringensis
(B) Agrobacterium schizogenesis
(C) Thermus aquaticus
(D) Agrobacterium tumefaciens
Answer: D
77. Which enzyme of the following is used as a marker for a lysosomal fraction?
(A) Pyruvate dehydrogenase
(B) Phospholipase
(C) Acid phosphatase
(D) Succinate dehydrogenase
Answer: C
78. The formation of the Z ring in bacteria is important for :
(A) Septum formation
(B) Formation of pill
(C) Helpful in attachment
(D) Useful in movement
Answer: A
79. Which of the following is NOT true of Spermatogenesis?
(A) Four gametes are formed per meiosis
(B) Sex chromosomes are excluded from recombination and transcription during the first meiotic prophase
(C) Meiosis occurs continuously in mitotically dividing stem cells
(D) Differentiation of the gamete occurs; while in diploid, during the first meiotic prophase
Answer: D
80. A population of cells grown in adherent culture contains 0.4 mg protein per 106 cells. Actin comprises 4. 5% of the total protein. Given the Mr of actin is 42000 daltons and Avogardo number is 6. 02 × 1023 which of the following equals the mean number of actin molecules per cell?
(A) 2.58 × 1014 actin molecules
(B) 2.58 × 1014 actin molecules
(C) 2.58 × 108 actin molecules
(D) 2.58 × 1010 actin molecules
Answer: C
81. Which of the following is a natural dye obtained from the plant?
(A) Acid fuchsin
(B) Haematoxylin
(C) Carmine
(D) Aniline blue
Answer: B
82. The groups which are evolved from more than one ancestor are known as:
(A) Monophyletic
(B) Paraphyletic
(C) Polyphyletic
(D) Heterophyletic
Answer: C
83. Which of the following is an example of a symmetrical animal?
(A) Hydra
(B) Frog
(C) Sponges
(D) Sea Anemone
Answer: A, B, C, D
84. Which of the following chemical mutagens are incorporated into the genome by the DNA polymerase during genome replication?
(A) Alkylating agents
(B) Base analogs
(C) Deaminating agents
(D) Intercalating agents
Answer: B
85. Progesterone:
(A) Is synthesized in the hypothalamic neurons and stored in the posterior pituitary
(B) Plays a major role in preparing the uterus for implantation
(C) Is a protein hormone and is solely responsible for the maintenance of secondary sex characteristics
(D) Is exclusively responsible for stimulation of FSH production and follicle growth
Answer: B
86. When somatic cells of ovule directly form embryos, the phenomenon is called as
(A) Adventive embryony
(B) Diplospory
(C) Apospory
(D) Parthenogenesis
Answer: A
87. Globin synthesis in the absence of heme in RBC is regulated by the phosphorylation of this factor:
(A) EF1
(B) eIF2
(C) EFG
(D) eIF3
Answer: B
88. In anaerobic glycolysis, 2 moles of inorganic phosphate are used per mole of glucose consumed. Which of the following enzymes catalyzes the uptake of inorganic phosphate?
(A) Hexokinase
(B) Phosphofructokinase
(C) Glyceraldehyde 3-phosphate dehydrogenase
(D) Pyruvate kinase
Answer: C
89. When oxygen reacts with rubisco enzyme the following products will be formed?
(A) 3-phosphoglycerate and 2-phosphoglycolate
(B) Two molecules of 3-phosphoglycerate
(C) Two molecules of 2-phosphoglycolate
(D) Glyceraldehyde 3-phosphate and 2-phosphoglycolate
Answer: A
90. Which one of the following is a functional excretory unit of cephalochordata?
(A) Nephridia
(B) Flame cell
(C) Solanocytes
(D) Nephron
Answer: A
91. Weismann proposed the theory of:
(A) Continuity of germplasm
(B) Continuity of protoplasm
(C) Continuity of plasma cells
(D) Continuity of cytoplasm
Answer: A
92. RAPD marker is:
(A) Recessive
(B) Co-dominant
(C) Dominant
(D) Partially dominant
Answer: C
93. Which of the following chromosomal aberration results in the formation of dicentric and acentric chromosomes?
(A) Paracentric inversion
(B) Pericentric inversion
(C) Reciprocal translocation
(D) Deletion
Answer: A
94. In a hypothetical diploid animal species, there is a locus with two alleles A and B. If A and B are co-dominant, then how many different phenotypes are possible in this species?
(A) 1
(B) 2
(C) 3
(D) 4
Answer: C
95. If a woman having blood group A with |A|O genotype married a man having a blood group with |B|B genotype, the expected proportion of heterozygotes among their children is:
(A) 25%
(B) 50%
(C) 75%
(D) 100%
Answer: D
96. Type of migration where marine fishes migrate to freshwater for their reproduction is:
(A) Anadromus
(B) Catadromus
(C) Oceanodromus
(D) Potamodromus
Answer: A
97. The propeller twist in the B-form of DNA is approximate:
(A) 30°
(B) −30°
(C) 36°
(D) −36°
Answer: C
98. The protein binding site in DNA can be identified by the following experiment:
(A) DNA footprinting
(B) Mobility shift assay
(C) Western blotting
(D) DNA fingerprinting
Answer: A
99. Noble laureate Barbara McClintock observed frequent breakage of maize chromosome 9 due to which of the following transposons?
(A) IS (Insertion elements)
(B) AC-Ds (Activator-Dissociator elements)
(C) Mu (Mutator)
(D) Spm/En (Suppressor-Mutator/enhancer)
Answer: B
100. Red-green color blindness is an example of …… genetic disorder.
(A) X-linked recessive
(B) X-linked dominant
(C) Y-linked recessive
(D) Y-linked dominant
Answer: A