Question

the electron transport system takes energy from ______ to pump protons across the thylakoid membrane.

○ excited electrons
○ overcharged neutrons
○ photons
○ quarks

Explanation:

In photosynthesis, the electron transport system in the thylakoid membrane uses energy from excited electrons (released from chlorophyll after absorbing photons) to pump protons. Overcharged neutrons, quarks are not involved in this process, and photons directly excite electrons but the electron transport chain uses energy from the excited electrons' movement. So the correct option is excited electrons.

Answer:

A. excited electrons