Question

1. what enzyme is used in the electron transport chain to create atp?

a. citric acid b. pyruvate c. atp synthase

1. where does glycolysis occur?

a. cytoplasm b. mitochondria c. chloroplast

1. which process produces the largest amount of atp?

a. fermentation b. krebs cycle c. etc

1. the oxygen required by cellular respiration is reduced and becomes part of which molecule?

a. atp b. co₂ c. h₂o

Explanation:

• Question 7: ATP synthase is the enzyme that uses the proton gradient formed in the electron transport chain to synthesize ATP from ADP and inorganic phosphate. Citric acid is an intermediate in the Krebs cycle, and pyruvate is a product of glycolysis.
• Question 8: Glycolysis occurs in the cytoplasm. The mitochondria are the site of the Krebs cycle and the electron transport chain (for eukaryotes), and chloroplasts are involved in photosynthesis.
• Question 9: The electron transport chain (ETC) produces the largest amount of ATP. Fermentation produces a small amount of ATP (2 ATP per glucose in glycolysis, and no additional ATP in the fermentation step itself in terms of net gain compared to aerobic respiration's ETC - which can produce around 28 - 32 ATP per glucose). The Krebs cycle produces a relatively small number of ATP (directly, but also generates electron carriers for the ETC).
• Question 10: In cellular respiration, oxygen acts as the final electron acceptor in the electron transport chain. It is reduced (gains electrons) and combines with hydrogen ions to form water (\(H_2O\)). ATP is the energy - carrying molecule, and \(CO_2\) is produced in the Krebs cycle.

Answer:

1. C. ATP Synthase
2. A. cytoplasm
3. C. ETC
4. C. \(H_2O\)