Why are NADH and FADH2 necessities in the electron transport chain? A) They help form water.

B) They donate electrons.

C) They help break up CO2.

D) They pick up electrons.

NADH and FADH2 play a fundamental role in the electron transport chain because they PICK UP electrons (Option D).

NADH and FADH2 play a fundamental role in the electron transport chain because they pick up electrons (i.e., they are electron carriers) from one molecule and drop them off with another (Option D).

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the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus