Question

during which stage of cellular respiration is carbon dioxide produced? a. fermentation b. glycolysis c. electron transport chain d. citric acid cycle how do nadh and fadh2 function in cellular respiration? a. they combine with oxygen to produce atp. b. they store glucose in the cytoplasm. c. they carry electrons to the electron transport chain. d. they synthesize proteins in the mitochondrion. what is the significance of the citric acid cycle in cellular respiration? a. it generates nadh and fadh2 for the electron transport chain. b. it breaks down glucose into pyruvate. c. it occurs outside the mitochondrion. d. it directly produces water and oxygen.

Explanation:

• For the first question, carbon - dioxide is produced during the Citric Acid Cycle in cellular respiration. Fermentation can produce carbon - dioxide in some cases but is not a stage of aerobic cellular respiration. Glycolysis produces pyruvate, and the Electron Transport Chain mainly generates ATP.
• For the second question, NADH and FADH2 carry high - energy electrons to the Electron Transport Chain, where their energy is used to pump protons and generate ATP. They do not combine directly with oxygen to produce ATP, store glucose, or synthesize proteins.
• For the third question, the Citric Acid Cycle generates NADH and FADH2 which are used in the Electron Transport Chain to produce ATP. Glycolysis breaks down glucose into pyruvate, the Citric Acid Cycle occurs in the mitochondrial matrix, and it does not directly produce water and oxygen.

Answer:

1. d. Citric Acid Cycle
2. c. They carry electrons to the Electron Transport Chain.
3. a. It generates NADH and FADH2 for the Electron Transport Chain.