Which of the following processes is unique to cellular respiration?

• A. Protein synthesis
• B. DNA replication
• C. Oxidative phosphorylation
• D. Photosynthesis

Answer: (C)

Verified step by step guidance

1. Understand the context of cellular respiration: Cellular respiration is a metabolic process that converts glucose and oxygen into energy (ATP), carbon dioxide, and water. It primarily occurs in the mitochondria of eukaryotic cells.
2. Identify the unique process: Oxidative phosphorylation is a key step in cellular respiration that occurs in the inner mitochondrial membrane. It involves the electron transport chain and chemiosmosis to produce ATP.
3. Differentiate oxidative phosphorylation from other processes: Protein synthesis and DNA replication are general cellular processes that occur in all living cells, while photosynthesis is specific to autotrophic organisms like plants and algae. None of these are directly part of cellular respiration.
4. Explain oxidative phosphorylation: During oxidative phosphorylation, electrons are transferred through a series of protein complexes in the electron transport chain, creating a proton gradient across the mitochondrial membrane. This gradient drives ATP synthesis via ATP synthase.
5. Conclude why oxidative phosphorylation is unique: Oxidative phosphorylation is exclusive to cellular respiration and is essential for efficiently producing ATP, making it distinct from the other processes listed in the question.