13 PHOTOSYNTHESIS IN HIGHER PLANTS QUESTIONS
13 PHOTOSYNTHESIS IN HIGHER PLANTS QUESTIONS
Chlorophyll is the-
A) Red pigment of leaf of all plants
B) Blue pigment of leaf of all plants
C) Green pigment of root of all plants
D) None of these
In an experiment where a part of leaf is enclosed in test tube containing KOH Soaked Cotton & exposed to light will-
A) Test positive for starch
B) Test negative for starch due to inability to absorb light inside test tube
C) Test negative for starch due to inability to absorb CO2
D) Test negative for starch due to absence of water
Match the experiment objective with the scientist who performed it-
i) Priestly |
I) Production glucose in photosynthesis |
| ii) Julius von sachs | II) Role of sunlight in photosynthesis |
| iii) Jan ingenhousez | III) Role of air in photosynthesis |
(i) (ii) (iii)
(A) I III II
(B) II I III
(C) II III I
(D) III I II
Who performed a series of experiments that revealed the essential role of air on the growth of green plants and when?
A) Cornelius van Niel (1787)
B) Joseph Priestly (1770)
C) T. Engelmann (1756)
D) Both A and B
Who discovered oxygen and when?
A) Joseph Priestly (1770)
B) T. Engelmann (1770)
C) Jan Ingenhousz (1787)
D) Joseph Priestly (1774)
Who showed that sunlight is essential to the plant?
A) T. Engelmann
B) Joseph Priestly
C) Jan Ingenhousz
D) Cornelius van trial
part of the plants that could release oxygen.
A) Jan Ingenhousz
B) T. Engelmann
C) Joseph priestly
D) None of these
Match the following
(A) First action spectrum (1) Cornelius van nel
(B) Chlorophyll (2) T.W Engelmann
(C) O2 evolve from H2O (3) Algae
(D) Cladophora (4) Julius von sachs
(5) Bacteria
A) A-1, B-4, C-1, D-3,5
B) A-3, B-2, C-4, D-1
C) A-1, B-3, C-2, D-5
D) A-2, B-4, C-1, D-3
________ were used to detect the sites of O2 evolution.
A) Bacteria
B) Daze
C) Fungi
D) Virus
Cornelius van Neil studied on ____ to demonstrate that photosynthesis is essentially a light dependent reaction.
A) Cladophora
B) Purple and green bacteria
C) Red algae
(D) Both A and B
________ from a suitable oxidisable compound reduces CO2 to Carbohydrates.
A) Oxygen
B) Hydrogen
C) Carbon
D) Both A and B
Cladophora is-
A) Purple and green bacteria
B) Green bacteria
C) Red algae
D) Green algae
(A) – O2 evolved by the green plant comes from H2O, not from carbon dioxide.
(B) – This was proved by using Radio isotopic techniques.
A) Statement A is wrong and Statement B is right
B) Both Statement A and B are wrong
C) Statement B is wrong and Statement B is correct
D) Both Statement A and B are correct
Where does photosynthesis take place?
A) Green part of leaves
B) Green part of stem
C) Brown part of stem
D) Both A and B
Assertion – Chloroplasts usually align themselves along the walls of mesophyll cells.
Reason – They get optimum quantity of incident light by aligning along well.
Choose the correct option.
(A) Assertion and Reason are correct and Reason is correct explanation for Assertion
(B) Assertion and Reason are correct but is not the explanation of Assertion
(C) Assertion and Reason are both incorrect
(D) Assertion is correct but Reason is incorrect
Chloroplast is-
A) Single membrane organelle
B) Double membrane organelle
C) Triple membrane organelle
D) Not an organelle
Choose the incorrect statement from the following?
(A) There is no clear division of labour within chloroplast
(B) Chloroplast has membranous system which includes stroma as well
(C) Membrane system is responsible for trapping the light energy
(D) More than one of the above
Dark reaction-
A) is not light-dependent
B) occurs in darkness
C) is photochemical reaction
D) is indirectly light-dependent
Identify correct labelling.
(i) |
(ii) |
(iii) |
(iv) |
|
| A | A Starch
granule |
Lipid
droplet |
Stroma
lamella |
Grana |
| B | Starch
granule |
Lipid
droplet |
Grana | Stroma
Lamella |
| C | Lipid
droplet |
Starch
granule |
Grana | Stroma
Lamellae |
| D | Lipid
droplet |
Starch
granule |
Stroma
lamella |
Grana |
Sugar is synthesized-
A) Non-enzymatically in grana
B) Non-enzymatically in stroma
C) Enzymatically in grana
D) Enzymatically in stroma
Which of the following is correct?
A) Light reaction depends on dark reaction
B) Dark reaction depends on light reaction
C) Both of the above
D) None of the above
If a plant is kept in dark for a long time-
A) Starch will be synthesized in chloroplast
B) ATP will be synthesized in chloroplast but no starch
C) NADPH will be synthesized in chloroplast but no starch
D) None of these
Choose the incorrect option- During daytime-
A) ATP will be synthesized in chloroplast by light reaction
B) NADPH will be synthesized in chloroplast by light reaction
C) Starch will not be synthesized by dark reaction
D) None of these
The colour of leaf is due to-
A) Chlorophyll only
B) Chlorophyll, carotenoids only
C) Chlorophyll, carotenoids, xanthophyll
D) None of these
Leaf pigments are separated by-
A) Crystallization
B) Gel electrophorese
C) Blotting
D) Paper chromatography
Match the pigment with its colour –
I II
(i) Chlorophyll a (A) Blue green
(ii) Chlorophyll b (B) Yellow
(iii) Carotenoids (C) Yellow-green
(iv) Xanthophyll (D) Yelloworange
(i) (ii) (iii) (iv) (i) (ii) (iii) (iv)
A) A C B D
B) A C D B
C) A D B C
D) A D C B
Which is the most abundant plant pigment in the world?
A) Chlorophyll a
B) Chlorophyll b
C) Carotenoids
D) xanthophylls
Identity correct
i ii iii
A Chl a Chl b Carotenoid
B Carotenoids Chl a Chl b
C Chl b Chl a Carotenoids
D Chl b Carotenoids Chl a
Maximum absorption by chlorophyll a occors in-
A) blue & green region
B) ned & green region
C) blue & red region
D) yellow & red region
Assertion – Chlorophyll ‘a’ is the chief pigment associated with photosynthesis
Reason – Chlorophyll maximum absorption coincides with maximum photosynthesis.
Choose correct option –
A) Assertion & Reason are correct & Reason is correct explanation of Assertion
B) Assertion & Reason are correct but Reason is not correct explanation of Assertion
C) Assertion is correct & Reason is incorrect.
D) Assertion & Reason are incorrect.
Accessory pigments include
A) Chlorophyll a
B) Chlorophyll b
C) both of these
D) None of these
Accessory pigments
A) Pass on the energy to chl ‘a’
B) pass on the energy to primary acceptor
C) Use energy for photolysis of water
D) more than one option
Advantages of accessory pigments include
A) they help by photolyzing the water
B) they protect chl ‘a’ from photooxidation
C) they enable narrower range of wavelength of incoming light to be used for photosynthesis
D) both a & b
Light Reaction is also Known as-
A) photochemical phase
B) biosynthetic phase
C) both of these
D) None of these
Choose correct order of events in light reaction-
i) ATP & NADPH formation ii) Water Splitting
iii) Oxygen release iv) Light absorption
A) III IV II I
B) IV III I III
C) IV II III I
D) II III IV I
LHC stands for-
A) Late Harvesting Complex
B) Light Harvesting Complex
C) Light Hanging Complex
D) Late Hanging Complex
The naming of PS I & PS II was based on-
A) their discovery order
B) their functioning sequence
C) the scientist who named it
D) the components of the photosystem.
Which of the following is correct?
A) PS I is called P800
B) PS II is called P680
C) Both a & b
D) None of these
Reaction Centre is formed by-
A) Only one chlorophyll ‘a’ molecule
B) A few chlorophyll ‘a’ molecule
C) One chlorophyll ‘a’ and a few accessory
D) A few chlorophyll ‘a’ and a few accessory pigments.
Choose the incorrect statements-
A) Antennae is a light harvesting system
B) Contains accessory pigments
C) Does not include reaction centre
D) None of these
When the light energy is absorbed by PSII, it is-
A) Converted to mechanical energy
B) Used to excite electrons
C) Used to change configuration of RUBisCO
D) Both a & c
The movement of excited electrons in Noncyclic Photophosphorylation:
A) uphill in terms of reduction potential scale
B) downhill in terms of reduction potential scale
C) uphill and downhill in terms of oxidation-reduction potential scale
D) both A and C
The electrons excited form PS II-
A) get used up by the first electron acceptor.
B) get used up in the middle of its ETS pathway to PS I
C) get passed on to pigments of PS I
D) get partially used up in ETS and the rest is passed to PS I.
The electrons passed on by PS I to electron acceptor are-
A) the ones that were transferred to PS I from PS II
B) electrons from the water splatted.
C) electrons excited when PS I absorbs light.
D) All of these
Electrons from PS-I move downhill to a molecule of energy-rich-
A) NADP+
B) NAD+
C) FAD+
D) GTP
The Z scheme is named so because-
A) it was discovered by a scientist with ‘Z’ as initial letter of name
B) the carriers of ETS present in thylakoid membrane are in ‘Z’ shape.
C) it forms ‘Z’ shape when the carriers of ETS are arranged in sequence on redox potential scale.
D) both A & C
Identify the correct site for
I- water splitting, II-NADP+ reduction, IIIATP synthesis
I II III
A) I II III
B) II I III
C) III II I
D) III I II
Splitting of water is important-
A) for the O2 formation
B) for the electrons released
C) for the hydroxide ions released
D) for the H2 released
Water splitting is associated with-
A) PS I located on inner side of thylakoid membrane
B) PS II located on inner side of thylakoid membrane
C) PS I located on Outer stroma lamellae
D) PS II located on outer stroma lamellae membrane
The O2 is released in-
A) Lumen of thylakoid
B) Outer side of thylakoid
C) Stroma
D) Cytoplasm
Protons are released-
A) Lumen of thylakoid
B) Outer side of thylakoid
C) Stroma
D) Cytoplasm
The process of ATP synthesis in cells is/are-
A) Photo-phosphorylation
B) Oxidative phosphorylation
C) Phosphosynthesis
D) Both A & B
The order of working of the two photosystems is-
A) PS I → PS II
B) PS II → PSI
C) Any of these depending upon location
D) None of these
Non-cyclic photo-phosphorylation involves-
A) PS I
B) PS II
C) Both PS I & PS II
D) None of the these, only enzymes in stroma
End product of Z-scheme is-
A) ATP
B) Glucose
C) NADH + H+
D) Both A & C
Cyclic photophosphorylation involves-
A) PS I only
B) PS II only
C) Both PS I & PS II
D) None of these
Cyclic phosphorylation ends in formation of-
A) ATP only
B) Glucose only
C) NADPH + H+ only
D) Both A & C
A possible location of cyclic photophosphorylation under full light is condition.
A) Stroma
B) Stroma lamellae
C) Cristate
D) Outer membrane of chloroplast.
Assertion – Cyclic photophosphorylation occurs in stroma
Reason – Stroma membrane lacks PS II and NADP reductase.
Choose correct answer-
A) Both Assertion & Reason are correct and Reason is correct explanation for A
B) Both Assertion & Reason are correct but Reason is not correct explanation for Assertion
C) Assertion is correct but Reason is wrong
D) Both Assertion & Reason are wrong
ATP Synthesis is linked to _i_ graduate across a membrane in _ii_
(i) |
(ii) |
| A) Electron | Photosynthesis & respiration |
| B) Electron | Photosynthesis only |
| C) Proton | Photosynthesis and respiration |
| D) Proton | Photosynthesis but not respiration |
Which of the following statements is true?
A) the protons accumulate towards outer side of membrane in photosynthesis
B) the protons accumulate to wards inner side (lumen) of thylakoid in respiration.
C) The protons accumulate towards outer side of membrane of respiration thylakoid
D) None of these
The proton gradient may be formed in photosynthesis due to-
A) Splitting of water
B) Reduction of NAD+
C) Both A and B
D) None of these
Assertion – Protons move through photosystems, protons are transported across membrane.
Reason – Primary acceptor of electrons is an H carrier
A) Both Assertion & Reason are correct and Reason is explanation of Assertion
B) Both Assertion & Reason are correct and Reason is not the explanation for Assertion
C) Assertion is correct but Reason is not correct
D) Assertion & Reason both are incorrect
Which of these is an H carrier?
A) PS II
B) Ferredoxin
C) Plastocyanin
D) Plastoquinone
NADP reductase enzyme is located on ________ of thylakoid membrane.
A) Stroma side (outer side)
B) Lumen side (I,e. outer side)
C) Stroma Side (i.e. inner side)
D) Lumen side (i.e. inner side)
The proton gradient is also formed due to-
A) reduction of NAD+
B) reduction of NADP+
C) reduction of both NAD+ & NADP+
D) reduction of FAD+
Which of the following is true?
A) ATP & NADPH + H+ both are formed towards stroma.
B) ATP & NADPH + H+ both are formed in lumen of thylakoid
C) ATP is formed in lumen while NADPH + H+ is formed towards stroma.
D) NADPH + H+ formed in lumen while ATP is formed in stroma.
Identify correct labels-
(i) |
(ii) |
(iii) |
| A) PQ | PC | Cyt B6f |
| B) Cyt B6f | PQ | PC |
| C) PC | Cyt B6f | PC |
| D) PQ | Cyt B6f | PC |
Identify correct –
| I | II |
| A) High electrochemical gradient | Low Gradient |
| B) Low electrochemical gradient | High Gradient |
| C) High electrochemical gradient | High Gradient |
| D) Low electrochemical gradient | Low gradient |
Statement A – The accumulation of protons in stroma cause decrease in pH of stroma.
Statement B – The accumulation of proton in lumen cause formation of potential gradient across thylakoid membrane.
Select the correct option-
A) A is correct and B is incorrect
B) B is correct and A is incorrect
C) A & B are correct
D) A & B are incorrect
ATP formation occurs upon-
A) build up of potential gradient
B) break down of potential gradient
C) Both of these
D) None of these
The transmembrane channel in ATP synthase enzyme is formed by-
A) CF0
B) CF1
C) CF2
D) Both A & B
The transmembrane channel allows – across membrane for ATP synthesis
A) Osmosis of protons
B) Simple diffusion of proton
C) Facilitated diffusion of electron
D) Facilitated diffusion of proton
The ATP synthese has two parts I & II
I II
(A) CF0 CF1
(B) CF1 CF0
(C) CF CF0
(D) None
CF0 is –
A) embedded in chloroplast membrane
B) protruding on outer surface of chloroplast
C) protruding on inner surface of chloroplast membrane
D) None of these
CF1 is-
A) embedded in chloroplast membrane
B) protruding on outer surface of chloroplast membrane
C) protruding on inner surface of chloroplast
D) None of these
Conformational change in ____ makes ATP.
A) CF0
B) CF1
C) Both
D) None
For creating proton gradient across thylakoid membrane ________ .
A) Energy is used
B) No energy is used
C) Energy is released
D) None of these
The end products of light reaction are-
A) Stored till dark reaction takes place at right
B) immediately used up in next round of light reaction
C) transferred to the stroma from lumen to be used in biosynthetic reaction occurring in stroma
D) None of these
The products of light reaction are-
A) ATP only
B) ATP & NADPH
C) ATP, NADPH, O2
D) NADPH Only
O2 is-
A) used up in dark reaction in stroma
B) used up in dark reaction in lumen thylakoid
C) diffused out of chloroplast
D) more than one option is correct
Statement A – Biosynthetic reaction is independent of direct presence of light
Statement B – Biosynthetic process continues for some time after the light becomes unavailable and then stops.
A) Both A & B are correct
B) A is correct and B is incorrect
C) A is incorrect and B is correct
D) A & B are in correct
Calvin discovered that first CO2 fixation product is-
A) 3-carbon organic acid
B) 4-carbon organic acid
C) 5- carbon organic acid
D) 6-carbon organic acid
To discover the first CO2 fixation product, Calvin worked on-using-
A) algae, radioactive C12
B) fungi, radioactive C12
C) algae, radioactive C14
D) fungi, radioactive C14
The first product of CO2 fixation was identified to be in the Calvin cycle.
A) PGA
B) RUBP
C) Citric acid
D) OAA
In C4 pathway, first CO2 fixation product is same options as
A) PGA
B) RUBP
C) Citric acid
D) OAA
OAA and PGA stands for-
A) 3-phophoglyceric acid and oxalis ascetic acid respectively
B) 3-peptido glutaric acid and oxalis ascetic acid respectively
C) 3-phosphas glutamic acid and oxalis ascetic acid respectively
D) None of these
For a 3 carbon compound to be formed after CO2 fixation, the acceptor molecule is of-
A) 2-carbon
B) 3-carbon
C) 4-carbon
D) 5-carbon
RUBP stands for-
A) Ribulose Bisphosphate Carboxylaseoxygenase
B) Ribose Bisphosphate Carboxylaseoxygenase
C) Ribulose Bisphosphate
D) Ribose Bisphosphate Carboxylaseoxygenase
The Calvin cycle starts with ______ ends with
A) RUBisCo, regeneration of RUBisCo
B) RUBP, regeneration of RUBisCo
C) RUBP, regeneration of RUBP
D) PGA, regeneration of PGA
Calvin cycle-
A) occurs in C3 plants only
B) occurs in C4 plants only
C) occurs in both C3 & C4
D) None of these
The three steps in Calvin cycle are-
| i | ii | iii |
| A) Carboxylation | Oxidation | Regeneration |
| B) Reduction | Carboxylation | Regeneration |
| C) Carboxylation | Reduction | Regeneration |
| D) Carbonation | Reduction | Regeneration |
The most crucial step of Calvin cycle is-
A) Carbonation
B) Carboxylation
C) Reduction
D) Regeneration
Carboxylation is catalyzed by the enzyme-
A) RUBP
B) PEP
C) NADPH
D) None of these
RUBisCo has the activity of-
A) Carbonation
B) Oxygenation
C) Oxidation
D) None of these
Reduction involves Use of __________ molecules of ATP for fixed CO2 reduction
A) 1
B) 2
C) 3
D) 4
Reduction involves use of – molecules of NADPH to reduce fixed CO2.
A) 1
B) 2
C) 3
D) 4
For formation of 1 glucose molecule, how may turns of Calvin cycle is needed?
A) 3
B) 1
C) 2
D) 6
Regeneration of __(i)__ takes place at expense of __(ii)__ ATP & __(iii)__ NADPH.
| (i) | (ii) | (iii) |
| A) RUBP | 0 | 1 |
| B) RUBP | 1 | 0 |
| C) RUBisCo | 0 | 1 |
| D) RUBisCo | 1 | 0 |
Statement A – In CO2 fixation cycle, the molecules of ATP used is more than NADPH used.
Statement B – to meet the difference in number of ATP & NADPH used in dark reaction, cyclic phosphorylation take place.
Choose the correct option-
A) A is correct but B is wrong
B) B is correct but A is wrong
C) A & B are correct and A explains B
D) A & B are incorrect.
For formation of 1 glucose, how many molecules of ATP are required by C3 cycle?
A) 12
B) 16
C) 18
D) 10
For one glucose formation, how many NAD molecules are needed by C3 pathway?
A) 10
B) 12
C) 16
D) 18
C4 plants are adaptation of plants to-
A) wet regions (heavy rainfall)
B) polar regions
C) dry tropics
D) moist rainforest
(i) – C4 plants lack Calvin cycle
(ii) – C4 plants lack photorespiration
(iii) – C4 plants have more productivity than C3 plants
(iv) – C4 plants cannot tolerate higher temperature
How many of the above statements are incorrect?
A) 0
B) 1
C) 2
D) 3
First CO2 fixation product in C4 cycle is-
A) RBP
B) PEP
C) OAA
D) Malate
Bundle sheath cells are present in ____ around ____.
A) C4 plants, vascular bundles
B) C3 plants, vascular bundles
C) Both of these
D) None of these
Leaves with bundle sheath cells are said to show-
A) Krant anatomy
B) Kranz anatomy
C) Kent anatomy
D) Krez anatomy
Bundle sheath cells-
A) Allow gaseous exchange
B) Have intercellular spaces
C) Have large number of chloroplasts
D) All of these
Example of C4 plants is-
A) Rice
B) Maize
C) Soyabean
D) Both A and C
Primary CO2 acceptor in C4 plants is-
A) 3-carbon molecule RUBP
B) 3-carbon molecule PEP
C) 4-carbon molecule PEP
D) 4-carbon molecule OAA
Enzyme responsible for primary CO2 fixation in C4 plants is-
A) RUBisCO
B) PEPCase
C) Oxaloacetase
D) Phenolase
Which of the following is true?
A) C4 plants lack RUBisCO
B) Mesophyll cells of C4 plants lack RUBisCO
C) Bundle sheath cells of C4 plants lack RUBisCO
D) C3 plants lack RUBisCO
Primary CO2 fixation occurs in C4 plants in
A) Bundle sheath cells
B) Mesophyll cells
C) Any of the above
D) None of these
CO2 fixation in C4 plants occurs in-
A) Bundle sheath cells
B) Mesophyll cells
C) Both A and B
D) None of the above
OAA forms other four carbon acids which are transported. They are-
A) Malic acid and oxalic acid
B) Malic acid and aspartic acid
C) Succinic acid and aspartic acid
D) Succinic acid and glutamic acid
The figure shows
A) Krebs cycle
B) Calvin cycle
C) Hatch and Slack pathway
D) EMP pathway
In C4 pathway, RUBisCO is-
A) absent
B) present in mesophyll cells
C) present in bundle sheath cell
D) none of these
PEPcase enzyme is-
A) absent in mesophyll cells
B) present in bundle sheath cells
C) both A and B
D) None of these
Calvin cycle takes place in __(i)__ in all C3 plants in __(ii)__ in all C4 plants
(i) |
(ii) |
| (A) mesophyll cells | Mesophyll cells |
| (B) bundle sheath cells | Mesophyll cells |
| (C) mesophyll cells | Bundle sheath cells |
| (D) bundle sheath cells | Bundle sheath cells |
Identify correct labels-
| (i) | (ii) | (iii) |
| A) Firation | Decarboxylation | Regeneration |
| B) Transport | Firation | Regeneration |
| C) Regeneration | Transport | Fixation |
| D) Regeneration | Decarboxylation | Fixation |
Identify the A and B
| (i) | (ii) |
| A) mesophyll cells
|
mesophyll cells |
| B) bundle sheath cells | mesophyll cells |
| C) mesophyll cells
|
Bundle sheath cells |
| D) bundle sheath cells | Bundle sheath cells |
Read the following statements-
Statement A – Ribulose Bisphosphate is the most abundant enzyme in the world.
Statement B – Photorespiration doesn’t occur in C4 plants.
Choose the correct option-
A) A is correct and B is incorrect
B) B is correct and A is incorrect
C) A and B are correct
D) A and B are incorrect
RUBisCO has ________ when CO2 & O2 is equal.
A) greater affinity for CO2 than O2
B) greater affinity for O2 than CO2
C) equal affinity for CO2 & O2
D) no affinity for O2
In C3 plants-
A) Some O2 binds to RUBisCO and CO2 fixation increases
B) no O2 binds to RUBisCO
C) Some O2 binds to RUBisCO and CO2 fixation decrases
D) only O2 binds to RUBisCO
When O2 binds to RUBisCO, RUBP is converted to ________ and ________.
A) Phosphoglycerate, phosphoenolpyruvate
B) Phosphoglycerate, phosphoglycerate
C) Phosphoenolpyruvate, phosphoglycerate
D) Phosphoglycolate, phosphoglycerate
In photorespiration-
A) Sugar and ATP are formed
B) Sugar is formed but not ATP
C) ATP is formed but not sugar
D) Sugar and ATP are not formed
Assertion – Photorespiration doesn’t occur in C4 plants.
Reason – CO2 concentration at enzyme site is high in C4 plants.
Chose correct option-
A) Both Assertion and Reason are correct and Reason is correct explanation for
Assertion
B) Assertion is correct and Reason is wrong
C) Assertion is wrong and Reason is correct
D) Both Assertion and Reason are wrong
Photosynthesis is dependent on-
A) internal factors of plant
B) external factors of environment
C) both A and B
D) None of these
How many of the following are factors affecting photosynthesis? age of leaves, orientation of leaf, internal CO2 concentration, amount of chlorophyll, number of leaves
A) 4
B) 2
C) 3
D) 5
Blackman’s which law comes into effect when several factors affect any biochemical process?
A) Law of Limited Components (1910)
B) Law of Limiting Factors (1910)
C) Law of Limited Components (1905)
D) Law of Limiting Factors (1905)
According to Blackmann’s Law, the rate of chemical process is determined by the factor which
A) is nearest to its maximum value
B) is nearest to its minimum value
C) both A and B
D) none of these
The relationship between incident light and CO2 fixation rate at higher light intensity is-
A) rate is constant with increasing intensity
B) rate increases with increasing intensity
C) rate decreases with increasing intensity
D) none of these
At lower Light intensity, the rate of CO2 fixation-
A) is constant with increasing light intensity
B) increasing with increasing light intensity
C) decreases with increasing light intensity
D) none of these
Light saturation occurs at ________ of full sunlight.
A) 5%
B) 10%
C) 20%
D) 40%
Very big increase in light intensity causes-
A) increase in photosynthesis
B) decrease in photosynthesis
C) no change in photosynthesis rate
D) none of these
Which of the following is true?
A) CO2 is a major limiting factor for photosynthesis in nature
B) Light is rarely a limiting factor for photosynthesis in nature
C) Both of these
D) None of these
The concentration of CO2 beyond which the CO2 becomes damaging over longer periods is-
A) 0.03%
B) 0.04%
C) 0.05%
D) 0.08%
The CO2 fixation rates increases upto the CO2 concentration of-
A) 300 ppm
B) 400 ppm
C) 500 ppm
D) 800 ppm
At low light conditions, which of the groups respond positively to increase in CO2–
A) C3
B) C4
C) Both
D) None
At high light conditions, which of the groups respond positively to increase in CO2.
A) CO2
B) C4
C) Both
D) None
C4 plants show saturation at CO2 concentration of-
A) 240 𝜇𝑙𝐿-1
B) 360 𝜇𝑙𝐿-1
C) 450 𝜇𝑙𝐿-1
D) 540 𝜇𝑙𝐿-1
C3 plants show saturation for CO2 concentration at-
A) 450 𝜇𝑇L-1
B) 360 𝜇𝑙L-1
C) 540 𝜇𝑖𝐿-1
D) 240 𝜇𝑙𝐿-1
Assertion – Greenhouse crops like tomatoes and bell pepper are grown in CO2 enriched atmosphere for higher yields.
Reason – C4 plants respond to higher CO2 concentration by showing increased rate of photosynthesis.
Choose the correct option.
A) Both Assertion and Reason are correct and Reason is correct explanation for Assertion
B) Both Assertion and Reason are correct but Reason is not the explanation for Assertion
C) Assertion is correct but Reason is wrong
D) Assertion and Reason are wrong
Which of the reaction is more sensitive to temperature?
A) Light Reaction
B) Dark Reaction
C) Both of then are equal
D) None of the above
Which group of plants has a higher temperature optimum?
A) C4
B) C3
C) Both
D) None
Which of the following is true?
A) Tropical plants have higher temperature optimum than temperature plants
B) Temperature plants have higher temperature optimum than tropical plants
C) Temperature and Tropical have equal temperature optimum
D) Polar regions plants have highest temperature optimum
Water stress causes
A) reduced CO2 availability
B) leaf wilting
C) reduced surface area of leaf
D) All of these
In the given graph, in which region will plant not respond to increase in CO2 concentration?
A) A
B) B
C) C
D) None
Which of the following is not a product of light reaction of photosynthesis?
(a) ATP
(b) NADH
(c) Oxygen
(d) NADPH
Oxygen is not produced during photosynthesis by:
(a) Green sulphur bacteria
(b) Nostoc
(c) Chara
(d) Cycas
With reference to factors affecting the rate of photosynthesis, which of the following statements is not correct?
(a) Increasing atmospheric CO2 concentration up to 0.05% can enhance CO2 fixation rate.
(b) C3 plants respond to higher temperatures with enhanced photosynthesis while C4 plants have much lower temperature optimum.
(c) Tomato is a greenhouse crop which can be grown in CO2 – enriched atmosphere for higher yield.
(d) Light saturation for CO2 fixation occurs at 10% of full sunlight.
In a chloroplast, the highest number of protons are found in:
(a) Stroma
(b) Lumen of thylakoids
(c) Inter membrane space
(d) Antennae complex
Water soluble pigments found in plant cell vacuoles are
(a) Xanthophylls
(b) Chlorophylls
(c) Carotenoids
(d) Anthocyanins
Emerson’s enhancement effect and Red drop have been instrumental in the discovery of
(a) photophosphorylation and non-cyclic electron transport.
(b) two photosystems operating simultaneously.
(c) photophosphorylation and cyclic electron transport.
(d) oxidative phosphorylation.
A plant in your garden avoids photorespiratory losses, has improved water use efficiency, shows high rates of photosynthesis at high temperatures and has improved efficiency of nitrogen utilisation. In which of the following physiological groups would you assign this plant?
(a) C3
(b) C4
(c) CAM
(d) Nitrogen fixer
Chromatophores take part in:
(a) Growth
(b) Movement
(c) Respiration
(d) Photosynthesis
The structures that are formed by stacking of organized flattened membranous sacs in the chloroplasts are :
(a) Grana
(b) Stroma lamellae
(c) Stroma
(d) Cristae
The oxygen evolved during photosynthesis comes from water molecules. Which one of the following pairs of elements is involved in this reaction?
(a) Manganese and Potassium
(b) Magnesium and Molybdenum
(c) Magnesium and Chlorine
(d) Manganese and Chlorine
In photosynthesis the light-independent reactions take place at
(a) Photosystem-I
(b) Photosystem-II
(c) Stromal matrix
(d) Thylakoid lumen
Cytochromes are found in :
(a) Outer wall of mitochondria
(b) Cristae of mitochondria
(c) Lysosomes
(d) Matrix of mitochondria
Anoxygenic photosynthesis is characteristic of :
(a) Rhodospirillum
(b) Spirogyra
(c) Chlamydomonas
(d) Ulva
In Hatch and Slack pathway, the primary CO2 acceptor is
(1) Oxaloacetic acid
(2) Phosphoglyceric acid
(3) Phosphoenol pyruvate
(4) RubisCO
One scientist cultured Cladophora in a suspension of Azotobacter and illuminated the culture by splitting light through a prism. He observed that bacteria accumulated mainly in the region of:
(1) Violet and green light
(2) Indigo and green light
(3) Orange and yellow light
(4) Blue and red light
During non-cyclic photophosphorylation, when electrons are lost from the reaction centre at PS II, what is the source which replaces these electrons?
(1) Oxygen
(2) Water
(3) Carbon dioxide
(4) Light
Which of the following statements is incorrect?
(1) RuBisCO is a bifunctional enzyme
(2) In C4 plants, the site of RuBisCO activity is mesophyll cell
(3) The substrate molecule for RuBisCO activity is a 5-carbon compound
(4) RuBisCO action requires ATP and NADPH
In light reaction, plastoquinone facilitates the transfer of electrons from
1) PS-I to ATP synthase
2) PS-II to Cytb6f complex
3) Cytb6f complex to PS-I
4) PS-I to NADP
The oxygenation activity of RuBisCo enzyme in photorespiration leads to the formation of
1) 1 molecule of 4-C compound and 1 molecule of 2-C compound
2) 2 molecules of 3-C compound
3) 1 molecules of 3-C compound
4) 1 molecule of 6-C compound
The first stable product of CO2 fixation in sorghum is:
1) Oxaloacetic acid
2) Succinic acid
3) Phosphoglyceric acid
4) Pyruvic acid
Which of the following statements is incorrect?
1) Stroma lamellae have PS I only and lack NADP reductase.
2) Grana lamellae have both PS I and PS II
3) Cyclic photophosphorylation involves both PS I and PS II
4) Both ATP and NADPH + H+ are synthesized during non-cyclic photophosphorylation
Which one of the following in not true regarding the release of energy during ATP synthesis through chemiosmosis? It involves:
1) Breakdown of proton gradient
2) Breakdown of electron gradient
3) Movement of protons across the membrane to the stroma
4) Reduction of NADP to on the stroma side of the membrane
Production of Cucumber has increased manifold in recent years. Application of which of the following phytohormones has resulted in this increased yield as the hormone is known to produce female flowers in the plants:
1) ABA
2) Gibberellin
3) Ethylene
4) Cytokinin
Given below are two statements:
Statement I: The primary acceptor in plants is phosphoenolpyruvate and is found in the mesophyll cells.
Statement II: Mesophyll cells of plants lack RuBisCo enzyme
In the light of the above statements, choose the correct answer from the options given below.
1) Bothe statement I and statement II are correct
2) Bothe Statement I and Statement II are incorrect
3) Statement I is correct but Statement II is incorrect
4) Statement I is incorrect but Statement II is correct
What is the role of large bundle sheath cells found around the vascular bundles in plants?
1) To provide the site for photorespiratory pathway
2) To increase the number of chloroplast for the operation of Calvin cycle
3) To enable the plant to tolerate high temperature
4) To protect the vascular tissue from high light intensity