Physiology of Plants MCQs Part VII

1) The first carbohydrate
produced in the dark
phase of photosynthesis

a) Starch
b) Fructose
c) Phosphoglyceric acid
d) Phosphoglyceraldehyde

2) Pigment system I

a) Photolysis
b) Cyclic photophosphorylation
c) Noncyclic photophosphorylation
d) Oxidative phosphorylation

3) The Calvin cycle occurs
in the

a) Cytoplasm
b) Chloroplast
c) Glyoxysomes
d) Mitochondria

4) The cycle
was discovered by

a) Hill
b) Arnon
c) Hatch and Slack
d) Calvin

5) Light reactions
take place in the

a) Stroma
b) Grana
c) Cytoplasm
d) Endoplasmic reticulum

6) Tropical plants like sugarcane show high efficiency of fixation because of the
a) EMP pathway
b) TCA cycle
c) Hatch-Slack cycle
d) Calvin cycle

7) The trapping
centre of light
energy in photosystem
I is

a) P-660
b) P-680
c) P-700
d) P-720

8) Which of the following do not evolve oxygen
during photosynthesis?

a) Photosynthetic bacteria
b) Red algae
d) Blue-green algae

9) The dark reaction in photosynthesis is called so because it
a) Occurs more rapidly at night
b) Does not require light
c) Cannot occur during day time
d) Can occur only in shade

10) In plants combines with in the presence of
a) Deoxycarboxylase
b) RuDP carboxylase
c) PEP carboxylase
d) None of these

11) is
defined as the

a) Temperature coefficient
b) Scale of light quality
c) Respiratory coefficient
d) Constant quantum equation

12) In photosynthesis the energy formed is transferred in the form of
a) ADP
b) AMP + ADP
d) ATP

13) When a cell transfers light energy into chemical energy which of the following reactions take place?
a) ATP – iP = ADP
b) ADP + iP = ATP
c) GDP + iP = GTP
d) GDP + iP = GTP

14) Cyclic

c) ATP only

15) plants
are also known as

a) Calvin type
b) Emerson type
c) Hatch and Slack type
d) Calvin Bassham type

16) During ATP synthesis, electrons pass through
a) Water
b) Cytochromes

17) The role of PS I in photosynthesis is to
a) Release oxygen from water
b) Cause photolysis of water
c) Synthesize ADP

18) In pigment system I the active chlorophyll is
a) P-660
b) P-680
c) P-700
d) P-720

19) During the dark reactions of photosynthesis
a) a 6 C sugar is broken down into 3 C sugars
b) Water is split
c) carbon dioxide is assimilated
d) Chlorophyll is activated

20) Which of the following was most useful in tracing the steps of dark
reaction of photosynthesis?

a) X-rays

21) One of the following is indispensable for ATP synthesis:
a) Calcium
b) Phosphorus
c) Iron
d) Sulphur

22) When ATP is converted into ADP it releases
a) Hormones
b) Electricity
c) Energy
d) Enzymes

23) Through which of the following substances does the photosystem I pass an
electron to NADP during the light reactions?

a) Cytochrome
b) Ferredoxin
c) Plastocyanin
d) Plastoquinone

24) The ‘compensation point’ means the condition
a) When the entire food manufactured in photosynthesis remains unutilised
b) When the pot is watered just to meet the full requirement of the plant
c) When the rate of photosynthesis is equal to the rate of respiration
d) Where there is neither photosynthesis nor respiration

25) Photorespiration involves the
a) Krebs cycle
b) Glycolate cycle
c) Hatch-Slack cycle
d) Calvin cycle

26) Which of the following occurs during the dark phase of photosynthesis?
a) Hydrogen is released
b) ATP is produced
c) Molecular oxygen is released
d) PGAL is synthesized

27) The first step in the process of photosynthesis is
a) Absorption of light by chlorophylls of both PS I and PS II
b) Absorption of light by chlorophyll of PS I only
c) Absorption of light by chlorophyll of PS II only

28) Which of the following is not a chemosynthetic bacteria?
a) Nitrobacter
b) Beggiatoa
c) Azotobacter
d) Nitrosomonas

29) As the light intensity increases, the limiting factor in photosynthesis
will be

a) Water
b) Temperature

30) Which one of the following would not be a limiting factor for photosynthesis?
a) Oxygen
b) Light
c) Carbon dioxide
d) Chlorophyll

31) Starch is detected in food by its
a) Blue reaction with iodine solution
b) Granular form even if cooked
c) Presence of stored energy
d) White appearance

32) Which of the following is a rich source of carbohydrates, proteins and

a) Gram
b) Groundnut
c) Bean
d) Rice

33) Much of the starch is deposited in banana fruit as it matures. Which
of the following explains how the starch gets there?

a) Starch solution passes through cells such as companion cells to the fruit
b) Starch solution passes through the cells of phloem to the fruit
c) A sugar solution passes through the phloem cells to the fruit where it is changed to starch
d) Starch grains passes through the cells from the xylem to the fruit

34) The energy for the early growth of a developing bean plant embryo is obtained
directly from

a) Light from the sun
b) Water in the soil
c) Food in the soil
d) Food in the seed

35) Food is transported to the various parts of the plant through the
a) Root hairs
b) Phloem
c) Xylem
d) Stomata

36) Organic substances such as sugars are translocated through the phloem
This can be demonstrated by

a) Defoliation
b) Ringing the stem
c) Grafting
d) Root pressure

37) Translocation of sugar in flowering plants occurs in the form of
a) Maltose
b) Glucose
c) Sucrose
d) Starch

38) When the bark is stripped from a tree, the vital vascular tissue removed
is the

a) Cork cambium
b) Phloem
c) Vessels
d) Pith

39) The manufactured food in a plant moves from the leaves to other parts
through the

a) Pith
b) Xylem
c) Phloem
d) Cortex

40) Which of the following trees would die quickest?
a) Pruned
b) Hollow hearted
c) Girdled
d) Deciduous

41) Although a tree girdled up to the bast may survive for some time, it will
eventually die because

a) Sugars and other organic materials will not move upwards
b) Sugars and other organic materials would not move downwards
c) Water will not move upwards
d) Water will not move downwards

42) The removal of a ring of bark from the trunk of a tree eventually kills
it since

a) Mineral salts can not go up
b) Water cannot go up
c) Food does not travel down and the roots are starved
d) The exposed part becomes infected with fungi

43) The Munch mass flow hypothesis explains
a) Translocation
b) Transpiration
c) Translation
d) Transcription

44) In hollow-hearted plants
a) the root will die
b) the shoot will die
c) the root and shoot will die at the same time
d) Neither the root nor the shoot will die

45) In photosynthesis chlorophyll serves as the
a) Raw material
b) End product
c) Hydrogen acceptor
d) energy entrapper

46) In photosynthesis, hydrogen is transferred from the light reactions to the dark reactions by
a) DPN
b) DNA
c) ATP

47) Chlorophyll is present
a) In the grana of chloroplast
b) On the surface of chloroplast
c) Dispersed throughout the chloroplasts
d) In the stroma of chloroplasts

48) The first product of fixation
in the Hatch-Slack pathway in plants is

a) Formation of oxaloacetate by the carboxylation of phosphoenol phosphate (PEP) in the bundle sheath cells
b) Formation of oxaloacetate by the carboxylation of phosphoenol phosphate (PEP) in the mesophyll cells
c) Formation of phosphoglyceric acid in the mesophyll cells
d) Formation of phosphoglyceric acid in the bundle sheath cells

49) The synthesis of ATP both in photosynthesis and respiration is essentially
an oxidation process utilizing the energy from the following:

a) Carbon dioxide
b) Water
c) Electrons
d) Cytochromes

50) Starch and cellulose are compounds consisting of many units of
a) Amino acids
b) Fatty acids
c) Glycerol
d) Simple sugars

51) Which is the evidence to show that released in photosynthesis comes from water? CORRECT IMAGE
d) All the above

52) joins
the photosynthetic pathway during the

a) Light reactions
b) Dark reactions
c) Photosystem I
d) Photosystem II

53) In plants
the Calvin cycle

a) Occurs in the stroma of bundle sheath chloroplasts
b) Occurs in mesophyll chloroplasts
c) Occurs in the grana of bundle sheath chloroplasts

54) Which of the following element is a component of Ferredoxin?
a) Copper
b) Manganese
c) Zinc
d) Iron

55) The common immediate source of energy in cellular activity

a) DNA
b) RNA
c) ATP
d) NAD

56) Which one of the following crop plants is very efficient
converter of solar energy and whose net productive value
ranges from 2 Kg to

a) Sugarcane
b) Rice
c) Wheat
d) Bajra

plants are found among

a) Gramineae only
b) Monocots only
c) Dicots only
d) Monocots as well as dicots

58) The following is the site for the dark reactions of photosynthesis:

a) Grana lamellae
b) Stroma
c) Stroma lamellae
d) Thylakoids

59) In blue-green algae photosystem II contains
an important pigment concerned with photolysis
of water. It is called

a) B Carotene
b) Chlorophyll b
c) Cytochrome c
d) Phycocyanin

60) The rate of photosynthesis is maximum in
a) Green light
b) Blue light
c) Red light
d) Far-red light

61) The enzyme which catalyzes the photosynthetic

cycle is

a) RUDP carboxylase
b) PEP carboxylase
c) Carbonic anhydrase
d) None of these

62) Which of the following techniques has been
most useful for investigating Calvin Cycle?

a) Flashlight experiment
b) Radioactive isotope technique
c) X-rays technique
d) None of these

63) The photosynthetic pigments in the chloroplast are
embedded in the membrane of the

a) Thylakoids
b) Photoglobin
c) Matrix
d) Envelope of chloroplast

64) The exact mechanism of photosynthesis is
a process of converting light energy into
chemical energy. This was established by

a) Jean Senebier
b) Robert Hill
c) Ingen Housz
d) None of the above

65) Bacterial photosynthesis is different
from that of higher plants as

a) Energy is not fixed
b) Light is not required
c) Oxygen is not released
d) A host organism is required

66) The full form of ATP is
a) Adenosine tetraphosphate
b) Adenosine triphosphate
c) Adenosine diphosphate
d) Adenine triphosphate

67) Photosystem II occurs in the
a) Stroma
b) Grana
c) Surface of mitochondria
d) On cytochromes

68) The synthesis of ATP in photosynthesis
and respiration is essentially an oxidation
reduction process involving removal of

a) Oxygen
b) Phytochromes
c) Cytochromes
d) Electrons

69) In photosynthesis which one acts as
an electron acceptor?

c) Oxygen
d) None of these

70) Chlorophyll a and b essentially contain
one of the following metals:

a) Mg
b) Cu
c) Fe
d) Mn

71) The most important reaction or phenomenon
in the universe is

a) Photosynthesis
b) Carbonation
c) Reduction
d) Cation exchange

72) Who was awarded the Nobel prize for tracing
the path of carbon in the dark reaction of

a) Melvin Calvin 1961
b) Emerson 1970
c) Ruben and Kamen 1949
d) Benson 1952

photosynthesis does not occur in

a) Triticum vulgare
b) Zea mays
c) Euphorbia splendens
d) Saccharum officinarum

74) Algal scum floats on the surface
of water in the day time becauseCORRECT IMAGE

c) Algae become lighter in the daytime

75) The absorption spectrum of chlorophyll
a) Approximates the action spectrum of photosynthesis
b) Explains why chlorophyll is a green pigment
c) Shows that some colours of light are absorbed more than others
d) All of these

76) Pepco has an advantage compared
to rubisco. The advantage is thatCORRECTIMAGE

a) Pepco is present in both mesophyll and bundle sheath cells, Rubisco is not
c) Rubisco is subject to photorespiration but Pepco is not
d) Both B and C

77) The NADPH and ATP from the light
dependent reactions are used to

a) Reform the photosystem
b) Convert PGA to PGAL
c) cause Rubisco to fix carbon dioxide
d) Cause electrons to move along their pathways

78) CAM photosynthesis occurs in plants

a) Thin green leaves with reticulate venation
b) Thin green leaves with parallel venation
c) Fleshy green leaves
d) Thin coloured leaves

79) ATP formation during photosynthesis
is termed as

a) Phosphorylation
b) Photophosphorylation
c) Oxidative phosphorylation
d) None of the above

80) The
cycle is found in

a) Potato
b) Water hyacinth
c) Mustard
d) Corn

81) Which of the following
shows dimorphism of chloroplasts?

a) Sugarcane
b) Rice
c) Sugar beet
d) Potato

82) If plants stop their photosynthetic
activity, which gas will disappear?


83) Young fruits are green but develop
brilliant shades of colour during
ripening because

a) Of ageing
b) the chloroplasts are degraded to carotenes and xanthophylls
c) The amount of organic acid decreases
d) The amount of sugar increases

84) Pyrenoids are the centre of
the formation of

a) Enzyme
b) Starch
c) Protein
d) Fat

85) The dark reaction of photosynthesis
is known as

a) Cyclic photophosphorylation
b) Non-cyclic photophosphorylation
c) the Hill reaction
d) the Calvin cycle

86) The conversion of NADP to
occurs in

a) PS-I
b) PS-II
c) PS-I and PS-II
d) Photolysis of water

87) Non-cyclic photophosphorylation

c) ATP only

88) Which of the following does
not participate when the light
reaction synthesize only ATP?

a) PS-I
b) PS-II
c) Ferredoxin
d) Plastocyanin

89) The electrons excited from
pigment system-II pass directly

a) Ferredoxin
b) Plastocyanin
c) Plastoquinone
d) Carotenoids

90) During cyclic photo-phosphorylation
the electrons are transferred
from ferredoxin to

b) Plastoquinone
c) Plastocyanin

91) In the light reaction of photosynthesis,
chlorophyll is subjected to

a) Destruction
b) Permanent reduction
c) Oxidation and reduction
d) Neutralization

92) The unidirectional flow of electrons
in photophosphorylation takes
place in

a) Cyclic photophosphorylation
b) Non-cyclic photophosphorylation
c) Pseudocyclic photophosphorylation
d) All of above

93) Which of the following is obtained from during glucose manufacture?
a) Oxygen
b) Carbon
c) Both A and B
d) None of the above

94) Which type of phosphorylation
takes place in photosynthesis?

a) Cyclic
b) Non-cyclic
c) Both A and B
d) None of the above

95) ATP and have
been called by Arnon as

a) Oxidizing power
b) Assimilatory power
c) Both A and B)
d) None of the above

96) The enzymes of the dark reaction in plants are found in
a) Bundle sheath chloroplasts
b) Mesophyll chloroplasts
c) a and b
d) None of the above

97) The family in
which many plants
are type

a) Malvaceae
b) Solanaceae
c) Crucifereae
d) Graminaceae

98) The photo-oxidation
of chlorophyll
is called

a) Intensification
b) Chlorosis
c) Solarization
d) Defoliation

99) Photosynthesis
takes place

a) Only in sunlight
b) Only in yellow light
c) In the visible light obtained from any source
d) Only in very high intensity of light

100) In cold
and foggy
areas, the
limiting factor

a) Temperature
b) Light
c) Both a and b
d) None of these


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