Photosynthesis MCQs

What is the primary pigment involved in photosynthesis?

• Carotenoids

• Chlorophyll a

• Xanthophyll

• Anthocyanin

Where does the light-dependent reaction of photosynthesis occur?

• Stroma

• Thylakoid membrane

• Cytoplasm

• Nucleus

Which gas is released as a by-product during photosynthesis?

• Carbon dioxide

• Oxygen

• Nitrogen

• Hydrogen

The source of oxygen released during photosynthesis is:

• Water

• Carbon dioxide

• Glucose

• ATP

Which enzyme is involved in carbon fixation during the Calvin cycle?

• RuBisCO

• ATP synthase

• PEP carboxylase

• Cytochrome oxidase

What is the main product of the Calvin cycle?

• Glucose

• ATP

• NADPH

• G3P (Glyceraldehyde-3-phosphate)

What is the first stable compound formed in the Calvin cycle?

• 3-PGA (3-phosphoglyceric acid)

• RuBP (Ribulose bisphosphate)

• Glucose

• PEP (Phosphoenolpyruvate)

Photosystems I and II are part of the:

• Light-independent reactions

• Light-dependent reactions

• Glycolysis

• Krebs cycle

What is the role of ATP and NADPH in the Calvin cycle?

• Electron donors

• Energy providers

• Pigments

• Carriers of CO₂

Which wavelength of light is most effective in photosynthesis?

• Green

• Yellow

• Blue and red

• Violet