Question

multiple choice question
how are photosystem ii and photosystem i in the chloroplast connected?
by a quinone molecule
by a chlorophyll b molecule
by nadph
by a cytochrome b6 - f complex

Explanation:

In the light - dependent reactions of photosynthesis, photosystem II and photosystem I in the chloroplast are connected by an electron transport chain. The cytochrome $b_6$-f complex is part of this electron - transport chain that shuttles electrons between the two photosystems. Quinone molecules are involved in the electron transport from photosystem II but are not the direct connection between the two photosystems. Chlorophyll b is a pigment and not involved in connecting the two photosystems. NADPH is a product of the overall light - dependent reactions and not the connecting link between photosystem II and I.

Answer:

By a cytochrome $b_6$-f complex