Which of the following is the best definition of cellular respiration?
a. a sequence of redox reactions with O₂ as the final electron acceptor
b. a sequence of redox reactions with the final electron acceptor from the environment
c. a method of generating ATP
d. the complete oxidation of glucose to CO₂ and H₂O
e. a series of reactions in which pyruvic acid is oxidized to CO₂ and H₂O

Verified step by step guidance

1. Identify the key components of cellular respiration, which include glycolysis, the Krebs cycle, and the electron transport chain.
2. Understand that cellular respiration involves redox reactions, where electrons are transferred from one molecule to another.
3. Recognize that the final electron acceptor in aerobic respiration is typically oxygen (O₂), which is reduced to form water.
4. Consider the complete oxidation of glucose, which involves breaking down glucose into carbon dioxide (CO₂) and water (H₂O), releasing energy in the form of ATP.
5. Evaluate each option to determine which one best encompasses the entire process of cellular respiration, including the role of oxygen and the complete oxidation of glucose.

Key Concepts

Cellular Respiration

Cellular respiration is a metabolic process through which cells convert nutrients, primarily glucose, into energy in the form of ATP. This process involves a series of biochemical reactions, including glycolysis, the Krebs cycle, and oxidative phosphorylation, where electrons are transferred through a series of carriers, ultimately leading to the production of ATP.

Redox Reactions

Redox reactions, or reduction-oxidation reactions, are chemical processes that involve the transfer of electrons between molecules. In cellular respiration, these reactions are crucial as they facilitate the conversion of energy stored in glucose into usable energy (ATP) by transferring electrons to oxygen, which acts as the final electron acceptor.

Final Electron Acceptor

The final electron acceptor is a molecule that receives electrons at the end of the electron transport chain during cellular respiration. In aerobic respiration, oxygen serves as the final electron acceptor, allowing for the complete oxidation of substrates like glucose, resulting in the production of water and carbon dioxide as byproducts.