Question

Where do the energy transfer molecules in the electron transport chain come from?

1) atp molecules produced during glycolysis and the citric acid cycle
2) pyruvate molecules produced during earlier phases of cellular respiration
3) nadh and fadH₂ molecules produced during glycolysis in the cytoplasm
4) nadh and fadH₂ molecules produced during earlier phases of cellular respiration

Answer 1

The energy transfer molecules in the electron transport chain come from NADH and FADH₂ molecules produced during earlier phases of cellular respiration, specifically glycolysis, and the citric acid cycle.

Step-by-step explanation:

The energy transfer molecules in the electron transport chain come from NADH and FADH₂ molecules produced during earlier phases of cellular respiration, specifically glycolysis, and the citric acid cycle. The energy transfer molecules in the electron transport chain come from NADH and FADH2 molecules produced during earlier phases of cellular respiration, including glycolysis in the cytoplasm and the citric acid cycle. These molecules donate high-energy electrons to carrier proteins within the membrane of the mitochondria, energizing the synthesis of ATP.

During glycolysis, glucose is converted to pyruvate, which is further converted to acetyl-CoA and enters the citric acid cycle. In both glycolysis and the citric acid cycle, NADH and FADH₂ molecules are produced. These molecules then donate high-energy electrons to energy carrier molecules in the electron transport chain, allowing for the production of ATP through chemiosmosis and oxidative phosphorylation.