During aerobic respiration, which of the following directly donates electrons to the electron transport chain at the lowest energy level?

During aerobic respiration, FADH₂ donates electrons to the electron

transport chain at the lowest energy level.

Aerobic respiration is the respiration that takes place in the presence of

oxygen. There are two main electron carriers in the electron transport chain

and they are NADH and FADH₂ .

NADH  donates electrons to the electron transport chain at the highest

energy level while FADH₂ donates electrons at the lowest energy level of the chain.

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FADH2(flavine adenine dinucleotide) is the electron donor of the electron transport chain at lowest energy level.

Explanation:

Aerobic respiration is the process whereby cellular energy is produce by using oxygen .

Electron transport chain is series of complexes that involves the movement of electrons from one molecule to another in order to release energy. NADH and FADH2 are the two major electron donor in electron transport chain.

NADH2 enter the electron transport chain through glycolysis, transformation of pyruvate to acetylcoa and citric acid while The two NADH enter the electron transport chain through citric acid. NADH2 is a good electron donor, it donates at high energy level while FADH2 is not good at donating electron so it's donate electron at lowest energy level.

An organisms niche is (A) The range of physical and biological conditions in which an organism lives and the way in which it uses those conditions.
 Technically, any of the answers could be true, however, A is the only one that offers a broad definition.A niche is not only the location and conditions in which an organism lives, but also the organisms role within that niche and how it uses the resources to survive.