Photosynthesis in higher plants MCQs with Answers

Question-1. When a photosynthetic plant is transferred to an atmosphere of enriched O2, its rate of

1. photosynthesis would decrease.
2. respiration would decrease
3. osmosis would increase
4. None of these

Question-2. When leaf cells are fully turgid, the transpiration rate is:

1. high
2. medium
3. low
4. not affected

Question-3. When the fluid outside a cell has a greater concentration of a given molecule than the fluid inside the cell, the external fluid is

1. isotonic
2. hypertonic
3. hypotonic
4. ultratonic

Question-4. Which element is located at the centre of the porphyrin ring in chlorophyll?

1. Manganese
2. Calcium
3. Magnesium
4. Potassium

Question-5. Which element is required in the germination of pollen grain?

1. Boron
2. Chlorine
3. Potassium
4. Calcium

Question-6. Which enzyme is most abundantly found on earth?

1. RuBisCo
2. Nitrogenase
3. Invertase
4. Catalase

Question-7. Which enzyme is most abundantly found on earth?

1. Catalase
2. Rubisco
3. Nitrogenase
4. Invertase

Question-8. Which fractions of the visible spectrum of solar radiations are primarily absorbed by carotenoids of the higher plants?

1. Violet and blue
2. Blue and green
3. Green and red
4. Red and violet

Question-9. Which of the following absorb light energy for photosynthesis?

1. Chlorophyll
2. Water molecule
3. O2
4. RuBP

Question-10. Which of the following are products of light reaction?

1. NADPH2 and Water
2. NADPH2 and ATP
3. ADP and ATP
4. NADPH2 and Glucose

Question-11. Which of the following are the principal photoreceptors in the chloroplast of green plants?

1. Chlorophyll b and c
2. Chlorophyll a and b
3. Chlorophyll and d
4. Chlorophyll d and c

Question-12. Which of the following colours of light work best for photosynthesis?

1. Red
2. Yellow
3. Blue
4. Both a and c

Question-13. Which of the following conditions in a plant cell would increase the uptake of water?

1. osmotic pressure is higher than the turgor pressure
2. osmotic pressure is equal to turgor pressure
3. osmotic pressure is less than the turgor pressure
4. both a and c

Question-14. Which of the following conducts water inside plant body?

1. phloem
2. xylem
3. cortex
4. pith

Question-15. Which of the following forces are responsible for the ascent of water in plant body?

1. atmospheric pressure
2. root pressure
3. transpiration pull
4. both b and c

Question-16. Which of the following is not necessary for photosynthesis?

1. CO2
2. Chlorophyll
3. H2O
4. Oxygen

Question-17. Which of the following is not true of the exudation of water?

1. water drops come out through stomata
2. water drops come out through hydathodes
3. water is forced out of the leaves by root pressu
4. water drops are not formed by dew

Question-18. Which of the following is obtained from posphoglyceraldehyde in the dark reaction of photosynthesis?

1. phosphoglyceric acid
2. glucose
3. carbon dioxide
4. plastoquinone

Question-19. Which of the following is the source of hydrogen in the glucose molecule formed during photosynthesis?

1. Water
2. CO2
3. ATP
4. NADP

Question-20. Which of the following is the worlds most common protein?

1. cellulose
2. ribulose biphosphate carboxylase
3. insulin
4. diastase

Question-21. Which of the following is true of chlorophyll?

1. absorbs all types of waves of sunlight
2. containing iron atom in the center
3. containing magnesium atom in the center
4. present in all cells of green plants

Question-22. Which of the following percentage of transpiration usually occurs through the stomata?

1. 30%
2. 50%
3. 60%
4. 90%

Question-23. Which of the following processes is responsible for the entry of water into root hair?

1. wall pressure
2. osmotic pressure
3. turgor pressure
4. atmospheric pressure

Question-24. Which of the following products of light reaction of photosynthesis is not used in the dark reaction?

1. ATP
2. NADPH2
3. Oxygen
4. None of these

Question-25. Which of the following statement is incorrect ?

1. C3 plants respond to higher temperature, show higher photosynthetic rate while C4 plants have lower optimum temperature
2. Tropical plants have higher temperature optimum than the plants adapted to temperate climate.
3. The effect of water as a factor is more through its effect on plant, rather than directly on photosynthesis
4. Light reaction is less temperature sensitive than dark reaction.

Question-26. Which of the following statements regarding photorespiration are true?

1. All of the above
2. Photorespiration results in a loss of usable carbon dioxide
3. Photorespiration is a metabolically expensive pathway
4. Photorespiration is avoided when CO2 is abundant

Question-27. Which of the following would occur when a plant cell is packed in a fluid with high osmotic concentration than the cell sap?

1. imbibition
2. Plasmolysis
3. Deplasmolysis
4. Diffusion

Question-28. Which one is a C4 plant?

1. Papaya
2. Pea
3. Potato
4. Maize/corn

Question-29. Which one occurs both during cyclic and non-cyclic modes of photophosphorylation?

1. Involvement of both PS-I and PS-II
2. Formation of ATP
3. Release of O2
4. Formation of NADPH

Question-30. Which one of the following is represented by Calvin cycle?

1. Reductive carboxylation
2. Oxidative carboxylation
3. Photophosphorylation
4. Oxidative phosphorylation

Question-31. Which one of the following is wrong in relation to photorespiration?

1. It is a characteristic of C3 -plants
2. It occurs’in chloroplasts
3. It occurs in day time only
4. It is a characteristic of C4-plants

Question-32. Which one of the following pigment does not occur in the chloroplast?

1. Anthocyanin
2. Xanthophyll
3. Carotene
4. Chlorophyll 'b'

Question-33. Which one of the following statements about cytochrome P450 is wrong?

1. It contains iron
2. It is an enzyme involved in oxidation reactions
3. It is a coloured cell
4. It has an important role in metabolism

Question-34. Which pair is wrong?

1. C3—Maize
2. C4—Kranz anatomy
3. Calvin cycle—PGA
4. Hatch and Slack Pathway—Oxalo acetic acid

Question-35. Which pigment is water soluble?

1. Anthocyanin
2. Chlorophyll
3. Carotene
4. Xanthophyll

Question-36. Which pigment system is inactivated in red drop?

1. PS-Iand PS-II
2. PS-I
3. PS-II
4. None of these

Question-37. Which technique has helped in investigation of Calvin cycle?

1. X-ray crystallography
2. X-ray technique
3. Radioactive isotope technique
4. Intermittent light

Question-38. With the increase of ions in the xylem its water potential becomes

1. more positive
2. more negative
3. zero
4. neutral

Question-39. Besides water and CO2, which is more essential a raw material for food formation

1. light
2. oxygen
3. NAD
4. mineral salt

Question-40. Discovery of Emerson effect has already shown the

1. two distinct photochemical reactions
2. light and dark reactions of photosynthesis
3. photophosphorylation
4. photorespiration

Question-41. In actively gro – wing young plants, the best data for estimating the rate of photosynthesis would be

1. ratio of oxygen evolved to carbon dioxide absorbed
2. increase in fresh weight
3. increase in dry weight
4. increase in carbohydrate

Question-42. Kranz anatomy is a feature of

1. C3 plants
2. CAM plants
3. C4 plants
4. All of these

Question-43. Light reactions of photosynthesis occurs in

1. stroma
2. thylakoid
3. grana
4. cytoplasm of cell

Question-44. Manganese is required in

1. Chlorophyll synthesis
2. Nucleic acid synthesis
3. Plant cell wall formation
4. Photolysis of water during photosynthesis

Question-45. Oxidative phosphorylation refers to

1. Anaerobic production of ATP
2. The citric acid cycle production of ATP
3. Production of ATP by chemiosmosis
4. Alcoholic fermentation

Question-46. The law of limiting factor was given by

1. Calvin
2. Blackman
3. Priestley
4. None of these

Question-47. The metabolic pathway which produces carbohydrate is

1. Calvin cycle
2. Glycolysis
3. Cyclic electron pathway
4. Krebs cycle

Question-48. The primary carbon dioxide acceptor in C4 cycle is

1. malic acid
2. phosphoenol pyruvate
3. rubisco
4. aspartic acid

Question-49. Translocation of sugar in flowering plants occurs in the form of

1. glucose
2. sucrose
3. starch
4. maltose

Question-50. Water stress causes

1. opening of stomata
2. increase in metabolic rate
3. wilting of leaves
4. lesser availability of carbon dioxide

Question-51. Where are thylakoids and grana located?

1. Lysosomes
2. Mitochondria
3. Chloroplasts
4. Golgi apparatus

Question-52. Which of the following is a 4-carbon compound?

1. Oxaloacetic acid
2. Phosphoglyceric acid
3. Ribulose biphosphate
4. Phosphoenolpyruvate

Question-53. Which of the following is not an accessory pigment?

1. Carotene
2. Chlorophyll a
3. Chlorophyll b
4. Xanthophyll

Question-54. Which of the following process (C4 cycle) occurs in bundle sheath cells?

1. Regeneration
2. Fixation
3. Carboxylation
4. Decarboxylation

Question-55. Which one of the following statement is true for ATP?

1. ATP is prosthetic part of an enzyme
2. ATP is an enzyme
3. ATP is organic ions of enzyme
4. ATP is a Co-enzyme

Question-56. Who enunciated the law of limiting factor for photosynthesis?

1. Robert Emerson
2. Ruben
3. Blackman
4. Calvin

Question-57. The rate of photosynthesis is controlled by

1. the rate of light reaction
2. the rate of dark reaction
3. the rates of both light and dark reactions
4. none of the above

Question-58. The end product of the Calvin cycle is

1. RuBP
2. PGAL
3. PGA
4. ADP + NADP

Question-59. In which of the following assimilates move along the concentration gradient?

1. sieve tubes
2. xylem vessels
3. trachieds
4. fibers

Question-60. A photosynthesizing plant is releasing 18O more than the normal. The plant must have been supplied with

1. O3
2. H2O with 18O
3. CO2 with 18O
4. C6H12O6 with 18O

Question-61. A photosystem is an assemblage of pigment molecules together ranging from

1. 10 – 100
2. 100 – 200
3. 200 – 400
4. 400 – 500

Question-62. A very efficient converter of solar energy with net productivity of 2-4 kg/m2 or more is the crop of

1. wheat
2. sugarcane
3. rice
4. bajra

Question-63. As a first identifiable product of the dark reaction is:

1. PGA
2. PGAL
3. Glucose
4. RuBP

Question-64. As compared to a C3-plant, how many additional molecules of ATP are needed for net production of one molecule of hexose sugar by C4-plants

1. 2
2. 6
3. 12
4. zero

Question-65. C4-cycle was discovered by

1. Hatch and Slack
2. Calvin
3. Hill
4. Arnon

Question-66. Chemiosmotic hypothesis given by Peter Mitchell proposes the mechanism of

1. synthesis of ATP
2. synthesis of NADH
3. synthesis of NADPH
4. None of these

Question-67. Chlorophyll "a" occurs in all Photosynthetic plants except:

1. Green algae
2. Blue green algae
3. Angiosperms
4. Pigment containing bacteria

Question-68. Chlorophyll in chloroplasts is located in

1. outer membrane
2. inner membrane
3. thylakoids
4. stroma

Question-69. Chlorophyll is a large molecule with a central core of:

1. Iron
2. Sulphur
3. Nitrogen
4. Magnesium

Question-70. Chlorophyll mainly absorbs red light and:

1. Green light
2. Yellow light
3. Blue light
4. Orange light

Question-71. Chlorophyll-a molecule at its carbon atom 3 of the pyrrole ring-II has one of the following

1. aldehyde group
2. methyl group
3. carboxyl group
4. magnesium

Question-72. Chlorophyll-a occurs in

1. all photosynthetic autotrophs
2. in all higher plants
3. all oxygen liberating autotrophs
4. all plants except fungi

Question-73. Chlorophylls c, d and e are present in:

1. Angiosperms
2. Gymnosperms
3. Bacteria
4. Algae

Question-74. Cytochrome is

1. metallo flavo protein
2. Fe-containing porphyrin pigment
3. glycoprotein
4. lipid

Question-75. Dark reactions of photosynthesis occur in

1. granal thylakoid membranes
2. stromal lamella membranes
3. stroma outside photosynthetic lamellae
4. periplastidial space

Question-76. During light reaction of photosynthesis, ATP formation occurs when electrons are transported between cytochrome:

1. a and b
2. b and c
3. b and f
4. c and f

Question-77. During monsoon, the rice crop of Eastern states of India shows lesser yield due to limiting factor of

1. CO2
2. light
3. temperature
4. water

Question-78. Ferredoxin is a constituent of

1. PS-I
2. PS-II
3. Hill reaction
4. P680

Question-79. Fixation of one CO2 molecule through Calvin cycle requires

1. 1 ATP and 2NADPH2
2. 2 ATP and 2NADPH2
3. 3 ATP and 2NADPH2
4. 2ATP and 1NADPH2

Question-80. Formation of ATP in photosynthesis and respiration is an oxidation process which utilises the energy from

1. cytochromes
2. ferredoxin
3. electrons
4. carbon dioxide

Question-81. Germination of seed involves the rupturing of seed coat because of:

1. Osmosis
2. Imbibitions
3. Diffusion
4. Active transport

Question-82. Grana are present inside the

1. chloroplast
2. ribosome
3. mitochondria
4. endoplasmic reticulum

Question-83. Greatest producers of organic matter are

1. crop plants
2. forests
3. plants of the land area
4. phytoplankton of oceans

Question-84. High energy electrons in photo system I are transferred from FRS to:

1. ATP
2. PC
3. NADP
4. PQ

Question-85. How many turns of Calvin cycle yield one molecule of glucose?

1. 8
2. 2
3. 6
4. 4

Question-86. In a CAM plant, the concentration of organic acid

1. increases during night
2. decreases or increases during day
3. decreases during the day
4. increases during the day.

Question-87. In C3-plants, the first stable product of photosynthesis during the dark reaction is

1. malic acid
2. oxaloacetic acid
3. 3-phosphoglyceric acid
4. phosphoglyceraldehyde

Question-88. In C4 plants, agranal chloroplasts are found in

1. bundle sheath cells
2. chloroplasts of guard cells
3. epidermal cell chloroplasts of green stem
4. mesophyll cells

Question-89. In C4-plants, Calvin cycle operates in

1. stroma of bundle sheath chloroplasts
2. grana of bundle sheath chloroplasts
3. grana of mesophyll chloroplasts
4. stroma of mesophyll chloroplasts

Question-90. In photosynthesis energy from light reaction to dark reaction is transferred in the form of

1. ADP
2. ATP
3. RuDP
4. chlorophyll

Question-91. In photosystem II, the electrons lost by reaction center are replaced by electrons from

1. H2O
2. C2 O
3. Photosystem I
4. ATP

Question-92. In photosystem-I the first electron acceptor is

1. an iron-sulphur protein
2. cytochrome
3. plastocyanin
4. ferredoxin

Question-93. In sugarcane plant 14CO2 is fixed in malic acid, in which the enzyme that fixes CO2 is

1. fructose phosphatase
2. ribulose bisphosphate carboxylase
3. phosphoenol pyruvic acid carboxylase
4. ribulose phosphate kinase

Question-94. In the dark reaction, ATP and NADPH2 react with:

1. RuBP
2. PGA
3. PGAL
4. Glucose

Question-95. In the leaves of C4 plants, malic acid formation during CO2 fixation occurs in the cells of

1. mesophyll
2. phloem
3. epidermis
4. bundle sheath

Question-96. In the photo system II, high energy electrons of chlorophyll molecule are accepted by:

1. PC
2. PQ
3. NAD
4. ATP

Question-97. Kranz anatomy is typical of

1. C4-plants
2. C3-plants
3. C2-plants
4. CAM plants

Question-98. Light reaction of photosynthesis occurs in:

1. Granum
2. Stroma
3. Mitochondria
4. Leucoplast

Question-99. Maximum solar energy is trapped by

1. planting trees
2. cultivating crops
3. growing algae in tanks
4. growing grasses

Question-100. NADPH is generated through

1. photosystem-I
2. photosystem-II
3. anaerobic respiration
4. glycolysis

Question-101. Nine-tenth of all photosynthesis of world (85-90%) is carried out by

1. large trees with millions of branches and leaves
2. algae of the ocean
3. chlorophyll containing ferns of the forest
4. scientists in the laboratories

Question-102. Of the total sunlight reaching the earth, the percentage used in the photosynthesis is:

1. 2%
2. 20%
3. 30%
4. 50%

Question-103. Oxygen gas released during photosynthesis is comes from:

1. Water
2. CO2
3. Glucose
4. None of these

Question-104. Photochemical reactions in the chloroplast are directly involved in

1. formation of phosphoglyceric acid
2. fixation of carbon dioxide
3. synthesis of glucose and starch
4. photolysis of water and phosphorylation of ADP to ATP

Question-105. Photophosphorrylation in a chloroplast is mot similar to which of the following mitochondrial reaction?

1. substrate-level phosphorylation
2. oxidative phosphorylation
3. oxidative decarboxylation
4. hydrolysis

Question-106. Photorespiration is favoured by

1. high O2 and low CO2
2. low light and high O2
3. low temperature and high O2
4. None of these

Question-107. Photosynthetic pigments found in the chloroplasts occur in

1. thylakoid membranes
2. plastoglobules
3. matrix
4. chloroplast envelope

Question-108. Photosynthetically active radiation is represented by the range of wavelength

1. 340-450 nm
2. 400-700 nm
3. 500-600 nm
4. 400-950 nm

Question-109. Photosystem I has an absorption spectrum of wavelengths of around

1. 600 nm
2. 650 nm
3. 680 nm
4. 700 nm

Question-110. Photosystem-II occurs in

1. stroma
2. cytochrome
3. grana
4. mitochondrial surface

Question-111. Pigment acting as a reaction centre during photosynthesis is

1. carotene
2. phytochrome
3. P700
4. cytochrome

Question-112. Plants do not store carbohydrates as glucose because it

1. dissolves in water, thereby altering the osmotic bala
2. attracts insects herbivores
3. is an unstable molecule
4. would replace ribose in DNA synthesis

Question-113. Protochlorophyll differs from chlorophyll in lacking

1. 2 hydrogen atoms in one of its pyrrole rings
2. 2 hydrogen atoms in two of its pyrrole rings
3. 4 hydrogen atoms in one of its pyrrole rings
4. 4 hydrogen atoms in two of its pyrrole rings

Question-114. Quantasomes are present in

1. chloroplast
2. golgi body
3. lysosome
4. None of these

Question-115. RuBisCO stands for

1. Ribulose Biphosphate Carboxylase Oxygenase
2. Ribulose Phosphate Carboxylase Oxygenase
3. Ribulose Phosphate Carboxylic Oxygenase
4. None of the above

Question-116. Stomata of CAM plants

1. never open
2. are always open
3. open during the day and close at night
4. open during the night and close during the day

Question-117. The break down of water molecule (photolysis) in photosynthesis occurs during:

1. light reaction
2. dark reaction
3. Glycolysis
4. Krebs cycle

Question-118. The carbon dioxide acceptor in Calvin cycle/ C3 plants is

1. Phosphoenol pyruvate (PEP)
2. Ribulose 1,5-diphosphate (RuDP)
3. Phosphoglyceric Acid (PGA)
4. Ribulose Monophosphate (RMP)

Question-119. The combined area of total stomatal pores as compared to the total leaf area is almost:

1. 1-2%
2. 3-4%
3. 5-6%
4. 7-8%

Question-120. The empirical formula of chlorophyll a is:

1. C55 H72 O5 N4 Mg
2. C55 H70 O5 N3 Mg
3. C56 H72 O66 N4 Mg
4. C55 H74 O5 N5 Mg

Question-121. The enzyme that catalyses initial carbon dioxide fixation in C4 plants is

1. RuBP carboxylase
2. PEP carboxylase
3. carbonic anhydrase
4. carboxydismutase

Question-122. The exudation of water drops from the leaves of intact plants is:

1. guttation
2. transpiration
3. evaporation
4. transportation

Question-123. The final acceptor of electrons during the light reaction of photosynthesis is:

1. Cyt. F
2. Cyt. B
3. ATP
4. NADP

Question-124. The first carbon dioxide acceptor in C 4-plants is

1. phosphoenol-pyruvate
2. ribulose 1,5-diphosphate
3. oxalo acetic acid
4. phosphoglyceric acid

Question-125. The first step of photosynthesis is

1. excitation of electron of chlorophyll by a photon of light
2. formation of ATP
3. attachment of CO2 to 5 carbon sugar
4. ionisation of water

Question-126. The most effective light absorbed by the chlorophyll is:

1. yellow
2. orange
3. green
4. none of these

Question-127. The movement of solvent molecules through a semi-permeable membrane from a region of low solute concentration to a region of high solute concentration is:

1. Diffusion
2. Plasmolysis
3. Osmosis
4. Active transport

Question-128. The number of stomata per square centimeter of leaf surface of tobacco leaf is almost:

1. 1200
2. 2100
3. 12000
4. 21000

Question-129. The organelles which take part in photo-respiration are

1. mitochondria, chloroplast, peroxisome
2. mitochondria, lysosomes, peroxisome
3. chloroplast, mitochondria, lysosome
4. chloroplast, mitochondria, nucleus

Question-130. The osmotic pressure of a solution

1. increases with increase in concentration of solute
2. decrease with increase in concentration of solute
3. remains unchanged with increase in concentration of sol
4. none of these

Question-131. The osmotic pressure of pure water is:

1. 1
2. 10
3. 100

Question-132. The principle of limiting factors was proposed by

1. Blackmann
2. Hill
3. Arnon
4. Liebig

Question-133. The process where by water moves through the plants is known as :

1. Transpiration
2. Translocation
3. Guttation
4. Osmosis

Question-134. The processes involved in stomatal transpiration are:

1. 2
2. 4
3. 8
4. 6

Question-135. The sequence of electron acceptors in the light reaction is

1. PQ—cyf f—cyt b—-PC
2. PQ—PC—Cytb—-Cyt f
3. PQ—PC—Cyt f—-Cytb
4. PQ—Cyt b—Cyt f—-PC

Question-136. The shrinkage of protoplasm due to ex-osmosis of water from the cell is called:

1. Osmosis
2. Deplasmolysis
3. Plasmolysis
4. Imbibition

Question-137. The substrate for photorespiration is

1. ribulose bis-phosphate
2. glycolate
3. serine
4. glycine

Question-138. The taking up of a liquid by a substance with the resultant swelling in volume is called:

1. Plasmolysis
2. Imbibitions
3. Diffusion
4. Active transport

Question-139. The transport of substances from a region of its lower concentration to its higher concentration is called:

1. Osmosis
2. Imbibition
3. Active transport
4. Passive transport

Question-140. The water of guttation is forced out of the leaves by:

1. Diffusion
2. Root Pressure
3. Imbibition
4. Active transport

Question-141. The water potential of all solutions as compared to pure water is always:

1. higher
2. lower
3. equal
4. none of these

Question-142. The wave lengths of red light are in the range of:

1. 400-500 nm
2. 500-550 nm
3. 600-650 nm
4. 700-750 nm

Question-143. The wavelengths of visible light are longer than the wavelengths of

1. infrared
2. ultraviolet
3. microwaves
4. radio waves

Question-144. Water in the xylem vessel will ascend up until

1. its cohesive and adhesive strength is more than the gravitational pull
2. gravitational pull is higher then the cohesive and adhesive strength of water
3. sufficient water is available in the soil
4. it is used in the photosynthesis

Question-145. Water potential of a liquid increases when solute concentration

1. Increases
2. Decreases
3. Remains unchanged
4. None of these