Physiology of Plants MCQs Part VI

1) The pigment system is concerned with the
a) Photolysis of water
c) Flowering of a plant
d) None of these

2) The role of chlorophyll in photosynthesis is the
b) Absorption of light
c) Absorption of light and photochemical decomposition of water
d) Absorption of water

3) In the process of photosynthesis chlorophyll functions as
a) A raw material
b) A hydrogen acceptor
c) An end-product
d) An energy converter

4) Chlorophyll is
a) Soluble in organic solvents
b) Soluble in water
c) Soluble in both organic solvents and water
d) None of the above

5) The oxygen which is liberated during photosynthesis comes from
a) Chlorophyll
b) Carbon dioxide
c) Phosphoglyceric acid
d) Water

6) A granum refers to
a) the glycolysis of glucose
b) A stack of thylakoids in the plastids of higher plants
c) a by-product of photosynthesis
d) A constant in quantum equations

7) Photophosphorylation is a process in which
a) Light energy is converted into chemical energy in the form of ATP
b) NADP is formed
c) Chemical energy is used to produce ATP
d) is
reduced to a carbohydrate

8) In photosynthesis, oxygen is liberated due to the
a) Reduction of carbon dioxide
b) Hydrolysis of carbohydrate
c) Photolysis of water
d) Breakdown of chlorophyll

9) Which wavelength of light carries out photosynthesis in bacteria?
a) Red
b) Far-red
c) Ultra violet
d) Blue

10) Where does the primary photochemical reaction occur in the chloroplast?
a) The periplast cavity
b) The inner membrane of the chloroplast
c) The quantasomes
d) The stroma

11) Light is necessary during photosynthesis for the
a) Evolution of hydrogen
b) Photolysis of water
c) Heating of the plant
d) Opening of stomata

12) For chlorophyll formation in plants, the elements needed are
a) Sodium and copper
b) Calcium and potassium
c) Iron and magnesium
d) Iron and calcium

13) The most effective wavelength of visible light in photosynthesis is
in the region of which of the following?

a) Red
b) Yellow
c) Violet
d) Green

14) The dry weight of a green leaf will be
a) Lesser in evening
b) Greater in the afternoon
c) Greater in morning
d) Almost same throughout the whole day

15) Which of the following is an essential part of photosynthesis?
a) Glycolysis
b) Photorespiration
c) Plasmolysis
d) Photolysis

16) The chemical phase in photosynthesis was discovered for the first time

a) Calvin
b) Blackman
c) Hill
d) Arnon

17) The first event in photosynthesis is the
a) Synthesis of ATP
b) Photoexcitation of chlorophyll and ejection of electrons
c) Photolysis of water
d) Release of oxygen

18) Chloroplasts fix
b) Hydrogen

19) During photosynthesis the oxygen in glucose comes from
a) Carbon dioxide
b) Water
c) Both carbon dioxide and water
d) Oxygen in the air

20) The basic structure of all chlorophylls comprises
a) A cytochrome system
b) Flavoproteins
c) a porphyrin system
d) Plastocyanins

21) The process of photophosphorylation was discovered by
a) Priestley
b) Warburg
c) Arnon
d) Calvin

22) A chloroplast contains the maximum quantity of
a) Pyruvic carboxylase
b) Hexokinase
c) RUDP carboxylase
d) None of the above

23) It is advantageous to use Hydrilla to demonstrate photosynthesis
rather than a land plant because

a) It respires slowly
b) It does not transpire
c) It photosynthesizes rapidly
d) Oxygen bubbles can be collected over water

24) Which pigment is absent in chloroplast?
a) Xanthophyll
b) Anthocyanin
c) Chlorophyll-a
d) Carotene

25) One of the following is a water soluble pigment:
a) Carotene
b) Chlorophyll
c) Anthocyanin
d) Xanthophyll

26) Algae float in water during the day time and sink at
night because

a) They become light due to consumption of food materials in respiration
b) They become buoyant in the daytime due to the accumulation of oxygen bubbles released in photosynthesis
c) They come up to enjoy sunshine
d) They lose weight at night

27) Which of the following is not a part of chlorophyll?
a) Iron
b) Nitrogen
c) Carbon
d) Hydrogen

28) Two chief functions of leaves are
a) Photosynthesis and respiration
b) Photosynthesis and transpiration
c) Transpiration and respiration
d) Respiration and digestion

29) Chlorophyll b is present in
a) Prokaryotes
b) Eukaryotes
c) Both prokaryotes and eukaryotes
d) Bacteria

30) What is common to photosynthesis and respiration?
a) Cytochrome
b) Light
d) Temperature

31) Photosynthesis is
a) A catabolic process
b) An anabolic process
c) An exothermic process
d) An exergonic process

32) For the process of photosynthesis all except one
of the following items are essential; point out the

a) Light, chlorophyll
b) Oxygen, sucrose
d) Water, minerals

33) The photochemical reactions of photosynthesis take place in the
a) Frets
b) Stroma
c) Thylakoids
d) All of these

34) The oxygen evolved in photosynthesis is
d) None of these

35) Leaves with yellow or colourless patches are termed as
a) Lecorine
b) Decolourized
c) Etiolated
d) Variegated

36) The percentage of light energy utilized for photosynthesis by higher plants is
a) 1 – 2
b) 10
c) 50
d) 100

37) It is appropriate that Chlorella (an alga) is taken for photosynthesis experiment, instead of land plant because
a) It respires slowly
b) It does not transpire
c) Oxygen coming out from it can be collected under water
d) It photosynthesizes at a faster rate

38) Besides water and light which is essential as a raw material for food formation?
c) Mineral salts
d) NAD

39) Photosynthesis is most active in
a) Green light
b) Red light
c) Yellow light
d) Sunlight

40) is
formed in all the following except

a) Burning of sugar
b) Respiration in plants
c) Photosynthesis by plants
d) On heating of limestone

41) Impure air is purified in the presence of light and green plants. This was
first said by

a) de Saussure
b) Priestley`
c) Van Helmont
d) Ingen Housz

42) The granum contains
a) 2-50 thylakoids
b) 2-100 thylakoids
c) 2-10 thylakoids
d) 2-20 thylakoids

43) In a chlorophyll molecule, the magnesium is situated in the
a) Isocyclic ring
b) Phytol chamber
c) Centre of the porphyrin ring
d) Corner of the porphyrin ring

44) Agranal chloroplasts occur in certain
a) Succulents
c) Hydrophytes

45) In a fish aquarium green aquatic plants are grown primarily for
a) Decoration
b) Fish food

46) The gas absorbed during photosynthesis is
a) Oxygen
b) Nitrogen
c) Ammonia
d) Carbon dioxide

47) The wavelength of green light is

48) In a photosynthesis experiment, plant growth could be best when exposed

a) Yellow and orange light
b) Blue and green light
c) Red and blue light
d) Green light

49) The ultimate biological energy comes from
a) Mitochondria
b) Sunlight
c) Glucose
d) ATP

50) During photosynthesis
a) Carbon dioxide and water both get reduced
b) Carbon dioxide and water both get oxidised
c) Water gets reduced and carbon dioxide oxidise
d) Carbon dioxide gets reduced and water oxidised

51) The alga used by Calvin and his co-workers in their experiments on photosynthesis

a) Chlamydomonas
b) Chlorella
c) Chara
d) Euglena

52) Which one of the following is a typical example of a

a) Maize
b) Arhar
c) Mango
d) Cotton

53) Radiant energy is stored in the form of chemical energy in
a) ATP
b) Stored food
c) RNA
d) DNA

54) Cyclic photophosphorylation operates under
a) Low light intensity and aerobic conditions
b) Optimum light and aerobic conditions
c) Low light intensity and anaerobic conditions
d) Under high concentration of oxygen

55) The isotope of carbon used extensively for studies in photosynthesis


56) The first step in photosynthesis is
a) Formation of ATP
b) Ionisation of water
c) Excitement of an electron of chlorophyll a by a photon of light

57) If half of the leaves of a plant are removed the rate of photosynthesis
will be

a) More and the photosynthetic yield will also be more
b) Less and the photosynthetic yield will also be less
c) More but the photosynthetic yield will be less
d) Less but the photosynthetic yield will be more

58) Which of the following proves that
is essential for photosynthesis?


59) Starch containing plastids are called
a) Amyloplasts
b) Chloroplasts
c) Chloroplasts
d) Chromoplasts

60) Thylakoids of grana possess the
a) Enzymes for Calvin cycle
b) Enzymes for photophosphorylation
c) Enzymes for C-3 pathway
d) Enzyme for C-4 pathway

61) In Angiosperms synthesis of chlorophyll occurs in the presence

a) Phytochrome
b) Light
c) Cytochrome
d) None of the above

62) Which of the following is least effective in photosynthesis?
a) Green light
b) Red light
c) Sunlight
d) Blue light

63) Which organism has a type of nutrition most similar to that
of animals?

a) Algae
b) Fungi
c) Lichens
d) Cyanobacteria

64) Agranal chloroplasts are a characteristic feature of one
of the following:

a) the bundle sheath of sugarcane leaves
b) the mesophyll of pea leaves
c) the bundle sheath of mango leaves
d) the mesophyll of maize leaves

65) The law of limiting factors in photosynthesis was enunciated

a) R.Hill
b) Liebig
c) Blackman
d) Krebs

66) Which one of the following statements is correct for chlorophyll

a) Chlorophyll a is found more than chlorophyll b in the leaves of most plants
b) Chlorophyll a and b are found in equal proportion in the leaves of most plants
c) Chlorophyll a is found less than chlorophyll b in the leaves of most plants
d) Chlorophyll b is found ten-fold more than chlorophyll a in the leaves of most plants

67) The balance between
is brought about by

a) Transpiration
b) Photosynthesis
d) Photo-respiration

68) Starch is insoluble in water yet it is accumulated in
large quantities in potatoes because

a) It is synthesized in the potato tuber itself
b) It is translocated from the leaves to the potato tuber in the form of sugar
c) Soil microorganisms deposit starch in the tuber
d) It is useful in consumption

69) Which of the following equations most adequately sums
up the photosynthetic reactions?


70) Which one of the following carbohydrates is a monosaccharide?
a) Glucose
b) Starch`
c) Sucrose
d) Cellulose

71) During the course of photosynthesis
a) ATP is formed
b) ATP is not formed
c) Oxygen evolved comes from carbon dioxide
d) Water is required as a medium but it does not take part in photosynthetic reactions

72) The rate of photosynthesis is higher in
a) Red light
b) Green light
c) Very high light
d) Continuous light

73) Which of the following is not required in the synthesis
of carbohydrates?

b) Chlorophyll
c) Nitrogen
d) Water

74) The primary acceptor during fixation in plants is
a) Ribulose bisphosphate
b) Glycolate
c) Phosphoenolpyruvate
d) Triose phosphate

75) That the oxygen evolved in photoynthesis comes from water was confirmed by using
d) Chlorine ions

76) The energy-rich substance in a cell is
b) DNA
c) ADP
d) ATP

77) The absorption of radiant energy from the sun is mainly
associated with

a) Ribosomes
b) Mitochondria
c) Chloroplasts
d) Cytoplasm

78) How many quanta are required to reduce one molecule
and produce one molecule of
in green plant photosynthesis?

a) 2 quanta
b) 8 quanta
c) 16 quanta
d) 32 quanta

79) The sequential energy changes in photosynthesis


80) The source of energy for carbon assimilation

a) Chlorophyll
c) Water
d) Sunlight

81) The production of ATP from ADP and inorganic
phosphate in the presence of light and chlorophyll is termed as

a) Phosphorylation
b) Oxidative phosphorylation
c) Photophosphorylation
d) Oxidative anabolism

82) Which of the following types of plastids are
commonly found in cells not exposed to light?

a) Leucoplast
b) Chloroplast
c) Chromoplast
d) None of the above

83) Most oxygen is released by
a) Bacteria
b) Animals
c) Algae
d) Fungi

84) The process of photosynthesis takes
place in

a) the roots only
b) the shoot only
c) All the cells of the plant
d) the chlorophyll containing cells only

85) The wavelength of infra-red light of
the spectrum is


86) fixation during the
pathway occurs in the chloroplast of

a) Guard cells
b) Mesophyll cells
c) Spongy parenchyma
d) Bundle sheath cells

87) Which one of the following is the
energy currency of the cell?

a) Phosphate
b) ATP
c) ADP
d) AMP

88) The Kranz type of anatomy is found inCORRECT IMAGE

89) Which of the following occurs during
light reactions of photosynthesis?

a) oxygen is combined with carbon dioxide
b) PGAL molecules are changed to

c) Water molecules are split
d) Carbon dioxide reacts with hydrogen

90) The plants are different from plants with reference to the
a) Type of pigments involved in photosynthesis
b) Type of end products of photosynthesis
c) Number of ATP that are consumed in preparing sugars
d) substance that accepts carbon dioxide in assimilation

91) The substrate for photorespiration is
a) Serine
b) Glycolic acid or Glycolate
c) Indole acetic acid
d) Malic acid

92) Cyclic photophosphorylation involves
a) Pigment I system
b) Pigment II system
c) Both pigment I and II system
d) None of the above

93) Which of the following is the
primary electron acceptor of Pigment
system I of photosynthetic organisation?

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

94) The role of chlorophyll in photosynthesis
is to

a) Absorb light
b) Photolyse water
c) Both A and B
d) None of these

95) Discovery of the Emerson Effect has shown the existence of
a) Light and dark reaction in photosynthesis
b) Two distinct photochemical reactions
c) Photorespiration
d) Photophosphorylation

96) The two-pigment system theory of photosynthesis was proposed by (or The evidence for the existence of two photochemical systems in photosynthesis was given by
a) Emerson
b) Hill
c) Arnon
d) Blackman

97) During the photochemical reactions
of photosynthesis


98) During photosynthesis when
PGA is changed into phosphoglyceraldehyde
which of the following reactions occur?

a) Oxidation
b) Hydrolysis
c) Electrolysis
d) Reduction

99) The synthesis of fructose in the
pathway occurs in the chloroplasts of the

a) Spongy mesophyll
b) Bundle sheath
c) Guard cells
d) Palisade tissue

100) In
plants carbon dioxide
is first absorbed in the

a) Bundle sheath
b) Mesophyll
c) Palisade parenchyma
d) Spongy parenchyma


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