What processes are involved in cellular respiration?

Cellular respiration is a fundamental metabolic process by which cells convert nutrients into energy, primarily in the form of ATP (adenosine triphosphate). The correct option outlines the main stages of cellular respiration: glycolysis, the Krebs cycle (also called the citric acid cycle), and oxidative phosphorylation.

Glycolysis is the first step in the process that occurs in the cytoplasm of the cell, where glucose is broken down into pyruvate, generating a small amount of ATP and NADH in the process. Following glycolysis, in the presence of oxygen, the pyruvate enters the mitochondria and undergoes the Krebs cycle. This cycle further breaks down the pyruvate, resulting in the production of carbon dioxide, ATP, and additional electron carriers like NADH and FADH2.

The final stage, oxidative phosphorylation, occurs in the inner mitochondrial membrane, where the NADH and FADH2 produced in previous steps are used to generate a large amount of ATP through the electron transport chain, coupled with oxygen as the final electron acceptor. This stage is crucial for the efficient production of ATP.

The other options do not accurately reflect the processes involved in cellular respiration. For instance, photosynthesis is a separate process entirely