Question

Which feature is

common to the electron transport chains of both photosynthesis and cellular respiration?
A. Oxygen
the terminal electron acceptor.
B.
Electrons flow in a cyclic pattern, with no terminal electron receptor.
C. Coupled reactions establish an electrochemical gradient across a membrane.
D. NADP+ is the terminal electron acceptor.

Answer 1

C. Coupled reactions establish an electrochemical gradient across a membrane.

Step-by-step explanation:

• During cellular respiration in mitochondria, and during photosynthesis in chloroplasts, the electron transport chain requires a proton gradient to pump protons across the membrane by active transport.
• Protons flow back across the membrane by facilitated diffusion through ATP synthase, which utilizes them to phosphorylate ADP to ATP.
• This process of ATP synthesis by harnessing the elctrochemicaal gradient geenrated by the diffusion of protons across the biological membrane through ATP synthase is called chemiosmosis.