This document contains an unsolved biology exam from 1994 containing 46 multiple choice questions testing knowledge of topics including ecology, physiology, evolution, and cell biology. The questions cover subjects such as the levels of DDT deposition in different organisms, the gas that contributes most to the greenhouse effect, the dominant second trophic level in a lake ecosystem, and the pacesetter of the heart.

1. AIPMT–PAST PAPERS
BIOLOGY- UNSOLVED PAPER - 1994

2. SECTION – I (Total Marks : 100)
 Single Correct Answer Type
 There are five parts in this question. Four choices are given for each part and one of them is
correct. Indicate you choice of the correct answer for each part in your answer-book by
writing the letter (a), (b), (c) or (d) whichever is appropriate

3. 01 Problem
Which among the following is likely to have the highest levels of D.D.T.
depositions in its body?
a. Sea gull
b. Phytoplankton
c. Eel
d. Crab

4. 02 Problem
Which one of the following gasses contributes maximum to the ‘green
house effect’ on the earth?
a. Carbon dioxide
b. Chlorofluoro carbon
c. Freon
d. Methane

5. 03 Problem
The dominant second trophic level, in a lake ecosystem, is
a. Phytoplankton
b. Zooplankton
c. Benthos
d. Plankton

6. 04 Problem
Sounds above what level are considered hazardous noise pollution?
a. Above 80 dB
b. Above 30 dB
c. Above 150 dB
d. Above 120 dB

7. 05 Problem
Which of the following species does not have the ability to fix atmospheric
nitrogen?
a. Azjitibactor
b. Anavaena
c. Nostoc
d. Spirogyra

8. 06 Problem
The most important human activity, leading to the extinction of wildlife, is
a. pollution of air and water
b. hunting for valuable wildlife products
c. introduction of alien species
d. alteration and destruction of the natural habitats

9. 07 Problem
if excess water passes out from the tissue without being restored by the
kidneys, the cells would
a. burst open and die
b. take water from the plasma
c. not be affected at all
d. Shriver and die

10. 08 Problem
Which one of the four parts mentioned below does not constitute of part of
single uriniferous tubule?
a. Distal convoluted tubule
b. Collecting duct
c. Bowman’s capsule
d. Loop of Henley

11. 09 Problem
The pace setter in the heart is called
a. Sino-atrial node (SAN)
b. Atrio-ventricular node (AVN)
c. Purkinje fibers
d. Papillary muscle

12. 10 Problem
Which of the following does not have an open circulatory system?
a. Frog’s tadpole
b. Prawn
c. Chelifer
d. Cockroach

13. 11 Problem
In man and mammals, air passes from outside into the lungs through
a. Nasal cavity, larynx, pharynx, trachea, bronchi, alveoli
b. Nasal cavity, larynx, pharynx, trachea, bronchioles, alveoli
c. Nasal cavity, pharynx, larynx, trachea, bronchioles, bronchi, alveoli
d. Nasal cavity pharynx, larynx, trachea, bronchi, bronchioles, alveoli

14. 12 Problem
Which of the following is correct pairing of site of action and substrate of
rennin?
a. Mouth-starch
b. Small intestine-protein
c. Stomach-casein
d. Stomach-fat

15. 13 Problem
What is true about cleavage in the fertilized egg in humans?
a. It starts while the egg is in fallopian tube
b. It starts when the egg reaches uterus
c. It is meroblastic
d. It is identical to the normal mitosis

16. 14 Problem
The heart sound ‘dup’ is produced when
a. Mitral valve is closed
b. Semi-lunar valves at the base of aorta get closed
c. Tricuspid valve is opened
d. Mitral valve is opened

17. 15 Problem
Two examples in which the nitrogenous wastes are excreted from body
in the form of uric acid are
a. Birds and lizards
b. Frogs and cartilaginous fishes
c. Insects and bony fishes
d. Mammals and mollusk

18. 16 Problem
The respiratory center, which regulates respiration, is located in
a. Cerebellum
b. Medulla oblongata
c. Cerebral peduncle
d. The vague nerve

19. 17 Problem
Prolonged deficiency of nicotinic and causes
a. Pellagra
b. Xerophthalmia
c. Osteomalacia
d. Anaemia

20. 18 Problem
The extra embryonic membranes of the mammalian embryo are derived
from
a. Trophoblast
b. Inner cell mass
c. Formative cells
d. Follicle cells

21. 19 Problem
In the 28 day human ovarian cycle, the ovulation takes place typically on
a. Day 14 of the cycle
b. Day 28 of the cycle
c. Day 1 of the cycle
d. Day 5 of the cycle

22. 20 Problem
The immediate cause of induction of ovulation in human female is the large
plasma surge of
a. LH
b. FSH
c. Progesterone
d. Estrodiol

23. 21 Problem
The type of joint between the human skull bones is called
a. Cartilaginous joint
b. Hinge joint
c. Fibrous joint
d. Synovial joint

24. 22 Problem
Which of the following components is a part of the pectoral girdle?
a. Sternum
b. Acetabulum
c. Glenoid cavity
d. Ilium

25. 23 Problem
Which of the following is the function of enterogastrone?
a. It inhibits the secretion of gastric juice
b. It stimulates the secretion of digestive juices in the stomach
c. It stimulates the flow of pancreatic juice
d. It regulates the flow of bile

26. 24 Problem
An epithelial tissue which has thin flat cells, arranged edge to so as to
appear like closely packed tiles, is found to be present at
a. Outer surface of ovary
b. Inner lining of fallopian tube
c. Inner lining of stomach
d. Inner lining of cheeks

27. 25 Problem
A plant bears fruit, has a column of vascular tissue and a tap root system. This
plant is a
a. Angiosperm and dicot
b. Gymnosperm and dicot
c. Angiosperm and monocot
d. Gymnosperm and monocot

28. 26 Problem
Haploid plants can be obtained by culturing
a. Pollen grains
b. Root tips
c. Young leaves
d. Endosperm

29. 27 Problem
Besides giving out secretory vesicles, the golgi apparatus is also concerned
with the formation of
a. Lysosomes
b. Plastids
c. Grana of chloroplasts
d. Cell plates after cell division in plants.

30. 28 Problem
Which one of the following changes involved is irrelevant, in the evolution of
man?
a. Perfection of hand for tool making
b. Change of diet from hard nuts and hard roots to soft food
c. Loss of tail
d. Increase in the ability to communicate with others and develop community
behavior

31. 29 Problem
Which of the following evidences does not favour the Lamarckian concept of
inheritance of acquired characters?
a. Lack of pigment in cave-dwelling animals
b. Melanization in peppered moth
c. Absence of limbs in snakes
d. Presence of webbed toes in aquatic birds.

32. 30 Problem
Coolum derived from blastocoels is known as
a. Pseudocoelom
b. Schizocoel
c. Haemocoel
d. Enterocoelom

33. 31 Problem
A common characteristic of al vertebrates without exception is
a. The division of body into head, neck, trunk and tail
b. Their body covered with an exoskeleton
c. The possession of two pairs of functional appendages
d. The presence of well-developed skull

34. 32 Problem
Tube feet are the characteristic structures of
a. Starfish
b. Jellyfish
c. Crayfish
d. Cuttlefish

35. 33 Problem
Among the following organisms point out a completely non-parasitic form
a. Tape worm
b. Mosquito
c. Sea anemone
d. Leech

36. 34 Problem
Which of the following is an example of platy helminthes?
a. Plasmodium
b. Schistosoma
c. Trypanosoma
d. Wuchereria

37. 35 Problem
Radial symmetry is, usually, exhibited in animals which
a. Are attached to the substratum
b. Have one opening of alimentary canal
c. Live in water
d. Have ciliary mode of feeding

38. 36 Problem
One of the special characters of coelenterate only is the occurrence of
a. Polymorphism
b. Flame cells
c. Hermaphrodites
d. Nematocysts.

39. 37 Problem
There are special proteins that help to open up DNA double helix in front of
the replication fork. These proteins are
a. DNA ligase
b. DNA toposiomerase I
c. DNA gyrase
d. DNA polymerase I

40. 38 Problem
There are special proteins that help to open up DNA double helix in front of the
replication fork. These proteins are
a. DNA ligase
b. DNA toposiomerase I
c. DNA gyrase
d. DNA polymerase I

41. 39 Problem
Initiation codon in eukaryotes is
a. GAU
b. AGU
c. AUG
d. UAG.

42. 40 Problem
The earliest fossil form, in the phylogeny of horse, is
a. Equus
b. Mesohippus
c. Eohippus
d. Merychippus

43. 41 Problem
Which of the following is pair of homologous organs?
a. Plectoral fin of rohu and fore-limb of horse
b. Wings of grasshopper and wings of crow
c. Lungs of rabbit and gills of rohu
d. Wings of bat and wings of butterfly

44. 42 Problem
Plants, but not animals, can convert fatty acids to sugars by a series
of reactions called
a. Photosynthesis
b. Kreb’s cycle
c. Glycolysis
d. Glyoxylate cycle.

45. 43 Problem
The inner membrane of the mitochondria is, usually, highly convoluted
forming a series of in foldings known as
a. Tylakoids
b. Lamellae
c. Cristae
d. Grana

46. 44 Problem
In a somatic cell cycle, DNA synthesis takes place in
a. G1 phase
b. Prophase of mitosis
c. S-phase
d. G2 phase.

47. 45 Problem
Which one of the following organelles is located near the nucleus and
contains a collection of flattened membrane bound cisternae?
a. Nucleolus
b. Mitochondrion
c. Centriole
d. Golgi apparatus.

48. 46 Problem
Centro mere is required for
a. Replication of DNA
b. Chromosome segregation
c. Pole ward movement of chromosomes
d. Cytoplasm cleavage.

49. 47 Problem
Which of the following represents the best stage to view the shape, size and
number of chromosomes?
a. Prophase
b. Metaphase
c. Interphase
d. Telophase.

50. 48 Problem
The first phase in the breakdown of glucose, in animal cell, is
a. Fermenation
b. Kerbl’s cycle
c. Glycolysis
d. E.T.S

51. 49 Problem
In protein synthesis, the polymerization of amino acids involves three steps.
Which one of the following is not involved in the polymerization of protein?
a. Termination
b. Initiation
c. Elongation
d. Transcription.

52. 50 Problem
In mitochondria, cristae act as sites for
a. Protein synthesis
b. Phosphorylation of flavoproteins
c. Breakdown of macromolecules
d. Oxidation – reduction reaction

53. 51 Problem
A red blood cell was kept in a solution for a few minutes, where is got burst.
The solution taken was
a. Hypotonic
b. Conce. Sugar solution
c. Isotonic
d. Hypertonic

54. 52 Problem
Which of the following organelles contain enzymes that have digestive
action?
a. Ribosomes
b. Polysomes
c. Plastids
d. Lysosomes.

55. 53 Problem
The four elements that make up 99% of all elements found in a living
system are
a. C, H, O and P
b. C, N, O and P
c. H, O, C and N
d. C, H, O and S

56. 54 Problem
When yeast ferments glucose, the products obtained are
a. Ethanol and CO2
b. Methanol and CO2
c. Ethanol and water
d. Water and CO2

57. 55 Problem
Which of the following organelles is related with genetic engineering?
a. Mitochondria
b. Plasmids
c. Golgi bodies
d. Lysosomes

58. 56 Problem
Organisms, which fix atmospheric nitrogen in soil, fall under the category of
a. Bacteria
b. Green algae
c. Soil fungi
d. mosses

59. 57 Problem
The colour blindness is more likely to occur in males than in females
because
a. The Y-chromosome of males have the genes for distinguishing colors
b. Genes for characters are located on the sex-chromosomes
c. The trait is dominant in males and recessive in females
d. None of these.

60. 58 Problem
A cell-coded protein that is formed in response to infection, with most
animal viruses, is called
a. Histone
b. Antibody
c. Mterferon
d. Antigen

61. 59 Problem
Which of the following statements is correct with reference to a test
tube baby?
a. Fertilization of the egg is effected outside the body; the fertilized egg
then placed in the womb of the mother where the gestation is
completed
b. Fertilization of the egg is effected in the female genital tract. It is
then taken out and grown in a large test tube
c. A prematurely born baby is reared in an incubator
d. Fertilization of the egg and growth of the embryo are affected in a
large test tube.

62. 60 Problem
Albinism is a congenital disorder resulting from the lack of the enzyme
a. Tyrosinase
b. Xanthine oxidase
c. Catalase
d. Fructokinase

63. 61 Problem
A disease caused by eating fish contaminated by industrial waste,
containing mercury compounds, is called
a. Osteosclerosis
b. Hashimoto”s oxidase
c. Bright”s disease
d. Minimata disease.

64. 62 Problem
Which one of the following is correctly matches a sexually transmitted
disease with its pathogen?
a. Syphilis-Treponema pallidium
b. Gobirrhoea-Entamoeba histolytica
c. Urethritis-Bacillus anthracis
d. Softsore-Bacillus brevis.

65. 63 Problem
Silk is produced by
a. Adult moth
b. Cocoon
c. Larva
d. Both (a) and (c).

66. 64 Problem
Which among the following is the real product of the honey bee?
a. Honey
b. Propolis
c. Pollen
d. Bee wax

67. 65 Problem
The main reason why antibodies could not solve all the problems of bacteria
mediated disease is
a. Decreased efficiency of the immune system
b. Insensitivity of the individual following prolonged exposure to antibiotics
c. Development of mutant strains resistant to antibodies
d. Inactivation of antibiotics by bacterial enzymes

68. 66 Problem
Tobacco mosaic virus (TMV) genes are
a. Single stranded RNA
b. Double stranded DNA
c. Proteinaceous
d. Double stranded RNA.

69. 67 Problem
Biological control of agricultural pests, unlike chemical control, is
a. Self perpetuating
b. Polluting
c. Very expensive
d. Toxic.

70. 68 Problem
Calcium deficiency in the body occurs in the absence of
a. Vitamin C
b. Vitamin D
c. Vitamin B
d. Vitamin E

71. 69 Problem
In cheese manufacture, the microorganisms are important for
a. The ripening only
b. The souring of milk only
c. The development of resistance to spoilage only
d. Both the souring and the ripening processes.

72. 70 Problem
Lac operon’ in E. coli, is induced by
a. ‘I’ gene
b. promoter gene
c.  -galactosidase
d. Lactose.

73. 71 Problem
Transduction in bacteria is mediated by
a. Plasmid vectors
b. Phage vectors
c. Cosmos
d. F-factors.

74. 72 Problem
Which one of the following statements is correct?
a. Legumes fix nitrogen only through the specialized bacteria that live
in their roots
b. Legumes fix nitrogen independently of the specialized bacteria
that live in their roots
c. Legumes fix nitrogen only through specialized bacteria that live in
their leaves
d. Legumes are incapable of fixing nitrogen.

75. 73 Problem
Which of the following necleotide sequences contains 4 pyrimidine bases?
a. GATCAATGC
b. GCUAGACAA
c. UAGCGGUAA
d. Both (b) and (c).

76. 74 Problem
A child’s blood group is ‘O’. The parent’s blood groups cannot be
a. A and B
b. A and A
c. AB and O
d. B and O.

77. 75 Problem
Which statement best explains the evolutionary advantage of meiosis?
a. Meiosis is necessary for sexual reproduction
b. Genetic recombination are possible from generation to generation
c. Meiosis alternates with mitosis for generation to generation
d. The same genetic system is passed on from generation to generation.

78. 76 Problem
A metastatic cancerous tumor is termed’ sarcoma’ if the disorder is in
a. Fibroblasts
b. Circulatory system
c. Immune system
d. Epithelial cells.

79. 77 Problem
Normally DNA molecule has A-T, G-C pairing. However, these owing to
rearrangements called
a. Frame-shift mutation
b. Tautomerisational mutation
c. Analog substitution
d. Point mutation.

80. 78 Problem
The genes, which remain confined to differential region of Y-chromosome,
are
a. Autosomal genes
b. Holandric genes
c. Completely sex-linked genes
d. Mutant genes.

81. 79 Problem
The process of mating of individuals, which are more closely related than the
average of the population to which they belong, is called
a. Heterosis
b. Self breeding
c. Inbreeding
d. Hybridization.

82. 80 Problem
The nuclease enzyme, which begins its attack from free and of a
polynucleotide, is
a. Polymerase
b. Endonuclease
c. Exonuclease
d. Kinase.

83. 81 Problem
The ultimate respiratory substrate, yielding maximum number of ATP
molecules, is
a. Glycogen
b. Ketogenic amino acid
c. Glucose
d. Amylose.

84. 82 Problem
Posions like cyanide inhibit Na+ efflux and K+ influx during cellular transport.
This inhibitory effect is reversed by an injection of ATP. This demonstrates
that
a. ATP is the carrier protein in the transport system
b. Energy for Na+-K+ exchange pump comes from ATP
c. ATP is hydrolyzed by ATPase to release energy
d. Na+-K+ exchange pump operates in the cell.

85. 83 Problem
During light reaction of photosynthesis, which of the following
phenomenon is observed during cyclic phosphorylation as well as non-
cyclic phosphorylation?
a. Release of O2
b. Formation of ATP
c. Formation NADPH
d. Involvement of PSI and PSII pigment systems.

86. 84 Problem
As a tree grows older, which of the following increases more rapidly in
thickness?
a. Heart wood
b. Sap wood
c. Phloem
d. Cortex.

87. 85 Problem
Caesarian strip occurs in a
a. Endodermis
b. Exodermises
c. Epicycle
d. Epidermis.

88. 86 Problem
The 1992 Nobel Prize for medicine was awarded to Edmond H. Fischer
and Edwin Jokers for their work concerning
a. Reversible protein phosphorylation as a biological regulation
mechanism
b. Isolation of the gene for a human disease
c. Human genome project
d. Drug designing involving inhibition of DNA synthesis of the pathogen.

89. 87 Problem
Precambrian is situated just behind apical meristem. Procambium gives
rise to
a. Primary vascular bundle
b. Vascular cambium
c. Cork cambium
d. Both (a) and (b).

90. 88 Problem
Which of the following pigments acts as a reaction centre durin photosynthesis?
a. Carotene
b. Phytochrome
c. P700
d. Cytochrome.

91. 89 Problem
Embryo sac represents
a. Megaspore
b. Mega gametophyte
c. Megasporophyll
d. Megagamete.

92. 90 Problem
When pollen of a flower transferred to the stigma of another flower of the
same plant, the pollination is referred to as
a. Autogamy
b. Geitonogamy
c. Xenogamy
d. Allogamy.

93. 91 Problem
If the growing plant is decapitated, then
a. Its growth stops
b. Leaves become yellow and fall down
c. Axillary buds are inactivated
d. Axillary buds are activated.

94. 92 Problem
The movement of auxin is largely
a. Centripetal
b. Basipetal
c. Acropetal
d. Both ‘a’ and ‘c’

95. 93 Problem
Rickettsiae form a group under
a. Viruses
b. Bacteria
c. Fungi
d. A category between viruses and bacteria.

96. 94 Problem
Hypanthodium is a specialized type of
a. Fruit
b. Inflorescence
c. Thalamus
d. Ovary.

97. 95 Problem
In bryophytes
a. Both generations are independent
b. Gametophytes are dependent upon saprophytes
c. Saprophytes complete their life cycle
d. Saprophytes are dependent upon gametophytes.

98. 96 Problem
In Pinus, the wing of the seed develops from
a. Ovuliferous scale
b. Integument
c. Nucellus
d. Bract.

99. 97 Problem
In chlorophyceae, the mode of sexual reproduction is
a. Isogamy
b. Anisogamy
c. Oogamy
d. All of these.

100. 98 Problem
The protests have
a. Only free nucleic and aggregates
b. Membrane bound nucleo proteins lying embedded in the cytoplasm
c. Gene containing nucleoproteins condensed together in loose mass
d. Nucleoprotein in direct contact with the rest of the cell substance.

101. 99 Problem
Mycorrhiza exhibits the phenomenon of
a. Parasitism
b. Symbiosis
c. Antagonism
d. Endemism.

102. 100 Problem
Many blue-green algae occur in thermal springs (hot water springs). The
temperature tolerance of these algae have been attributed to their
a. Mitochondrial structure
b. Importance of homopolar bonds in their proteins
c. Cell wall structure
d. Modem cell organization.

103. For solution visit www.vasista.net