Question

In which two steps is the reaction sequence coupled to ATP generation?

a) Glycolysis and Electron Transport Chain
b) Krebs Cycle and Fermentation
c) Glycolysis and Krebs Cycle
d) Fermentation and Electron Transport Chain

Answer 1

ATP generation in cellular respiration is primarily coupled with glycolysis and the electron transport chain, where glycolysis produces pyruvate that yields electron carriers for the ETC to generate ATP through oxidative phosphorylation.

Step-by-step explanation:

The reaction sequence coupled to ATP generation in two steps are glycolysis and the electron transport chain (ETC). During glycolysis, glucose is broken down into pyruvate, generating small amounts of ATP through substrate-level phosphorylation. Pyruvate then enters the citric acid cycle (Krebs Cycle), which yields electron carriers NADH and FADH2. These electron carriers then donate their high-energy electrons to the electron transport chain. The movement of electrons through the ETC drives the production of ATP via oxidative phosphorylation, making it one of the main sources of ATP in cellular respiration. Therefore, the correct answer is a) Glycolysis and Electron Transport Chain.