Photosynthesis Practice Questions Flashcards
What is the primary function of photosynthesis?
A) Convert glucose and light into CO2 and energy
B) Convert light energy into chemical energy stored in sugars
C) Convert oxygen into glucose using light energy
D) Absorb CO2 to release ATP
B) Convert light energy into chemical energy stored in sugars
Where does photosynthesis primarily occur in plants?
A) Root cells
B) Mesophyll cells
C) Epidermal cells
D) Xylem
B) Mesophyll cells
What part of the chloroplast houses the ETC during the light-dependent reactions?
A) Stroma
B) Thylakoid membrane
C) Intermembrane space
D) Outer chloroplast membrane
B) Thylakoid membrane
What is the role of stomata in photosynthesis?
A) Absorb sunlight
B) Control electron exchange carriers
C) Regulate gas exchange (CO2 entry and H2O + O2 exit)
D) Produce NADPH
C) Regulate gas exchange (CO2 entry and H2O + O2 exit)
What is the main pigment involved in capturing light energy?
A) Chlorophyll
B) Carotenoid
C) Xanthophyll
D) Anthocyanin
A) Chlorophyll
What molecule is the final electron acceptor in the light-dependent reactions?
A) NADP+
B) ATP
C) Oxygen
D) Chlorophyll
A) NADP+
What enzyme catalyzes the first step of carbon fixation in the Calvin Cycle?
A) ATP synthase
B) Rubisco
C) NADP reductase
D) Plastocyanin
B) Rubisco
Which one of the following is a product of the Calvin Cycle?
A) Oxygen
B) ATP
C) G3P (glyceraldehyde 3-phosphate)
D) NADP+
C) G3P (glyceraldehyde 3-phosphate)
The oxygen released during photosynthesis comes from what molecule?
A) CO2
B) ATP
C) Glucose
D) H2O
D) H2O
What is photophosphorylation?
A) ATP generation using light energy
B) ATP generation during respiration
C) Absorption of light by pigments
D) Reduction of NADP+
A) ATP generation using light energy
What distinguishes cyclic photophosphorylation from linear photophosphoryation?
A) It does not produce ATP.
B) It produces only NADPH.
C) It recycles electrons back to photosystem I.
D) It occurs in the Calvin Cycle.
C) It recycles electrons back to photosystem I.
Why is photorespiration considered wasteful?
A) It consumes NADPH without producing ATP.
B) It releases CO2 instead of fixing it.
C) It requires oxygen to produce sugars.
D) It produces excess oxygen.
B) It releases CO2 instead of fixing it.
How is ATP generated in the light-dependent reactions?
A) Oxidation of glucose
B) ATP synthase using a proton gradient
C) Carbon fixation in the Calvin Cycle
D) Transfer of high-energy electrons to NADP+
B) ATP synthase using a proton gradient
What is the fate of G3P produced in the Calvin Cycle?
A) All is used to regenerate Rubisco.
B) It is entirely converted to oxygen.
C) Some is used to synthesize sugars, starches, and other molecules.
D) It is stored as ATP.
C) Some is used to synthesize sugars, starches, and other molecules.
