Question

multiple choice question
what is the role of the antenna complex in noncyclic photophosphorylation?

○ pass electrons and the energy they contain from photosystem ii to photosystem i
○ capture energy from photons and funnel it to the reaction center
○ transfer nadph to the light - independent reactions
○ establish the proton gradient that powers chemiosmosis

Explanation:

1. Analyze the first option: The electron transport chain between photosystem II and photosystem I (like plastoquinone, cytochrome complex) is responsible for passing electrons between them, not the antenna complex. So this option is incorrect.
2. Analyze the second option: The antenna complex (also called light - harvesting complex) is made up of pigment molecules. Its function is to absorb photons (light energy) and then transfer this energy to the reaction center of the photosystem. This matches the known role of the antenna complex.
3. Analyze the third option: The transport of NADPH to the light - independent reactions (Calvin cycle) is mainly related to the movement of molecules within the chloroplast, and the antenna complex has no role in this process. So this option is incorrect.
4. Analyze the fourth option: The proton gradient for chemiosmosis in photophosphorylation is established by the movement of protons across the thylakoid membrane, which is related to the electron transport chain and the splitting of water, not the antenna complex. So this option is incorrect.

Answer:

B. capture energy from photons and funnel it to the reaction center