Assertion: Photorespiration interferes with the successful functioning of Calvin cycle.
Reason: Photorespiration oxidises ribulose1,5 biphosphate which is an acceptor of CO2 in Calvin cycle.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
A.
If both assertion and reason are true and reason is the correct explanation of assertion.
In the 1920s, the German biochemist Otto Warburg (1883-1970) discovered that plants consumed oxygen at a higher rate when they were illuminated. He also found that this increased rate of oxygen consumption inhibited photosynthesis. Stimulation of oxygen consumption by light is now referred to as photorespiration. Biochemical studies indicate that photorespiration consumes ATP and NADPH, the high-energy molecules made by the light reactions. Thus, photorespiration is a wasteful process because it prevents plants from using their ATP and NADPH to synthesize carbohydrates.
RuBISCO, the enzyme which fixes carbon dioxide during the Calvin cycle, is also responsible for oxygen fixation during photorespiration. In particular, carbon dioxide and oxygen compete for access to RuBISCO. RuBISCO's affinity for carbon dioxide is much higher than its affinity for oxygen. Thus, fixation of carbon dioxide typically exceeds fixation of oxygen, even though atmospheric carbon dioxide levels are about 0.035% whereas oxygen is about 21%.
C4 plants have better productivity because
C4 plants absorb more light
C4 plants absorb more CO2
C4 plants does not carry photorespiration
C4 plants have more amount of RuBisCO
Photorespiration shows formation of
sugar but not ATP
ATP but not sugar
both ATP and sugar
neither ATP nor sugar
Which of the following is correctly labelled for the given figure
A: PS II; B : PS I; C :e- acceptor, D: LHC
A: LHC; B:e- acceptor; C: PS I; D: PS II
A: PS I; B:PS II; C:e- acceptor; D: LHC
A: e- acceptor; B : LHC; C: PS Il; D: PS I
Assertion : The efficiency of C4 plant is more than those of C3 plant.
Reason : C4 plants are more efficient in picking CO2.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are hue but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
The first stable product of Calvin cycle is
3- phosphoglycerate
1, 3 biphosphoglycerate
glyceralydehyde - 3 phosphate
ribulose - 5 - phosphate
Assertion : Due to pollution atmospheric concentration of CO2 is increasing which will be harmful for C4 plants whereas productivity is going to increase for C3 plants.
Reason : C4 plants have greater efficiency for CO2 as CO2 is fixed by PEP oxygenase.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
