Which cellular process primarily occurs in mitochondria in eukaryotic cells?

• A. Glycolysis
• B. DNA replication of the nuclear genome
• C. Oxidative phosphorylation (electron transport chain and ATP synthesis)
• D. Protein synthesis on ribosomes bound to the rough endoplasmic reticulum

Answer: (C)

Verified step by step guidance

1. Identify the main functions of mitochondria in eukaryotic cells, focusing on energy production processes.
2. Recall that glycolysis occurs in the cytoplasm, not in mitochondria, so it can be excluded.
3. Understand that DNA replication of the nuclear genome happens in the nucleus, not in mitochondria.
4. Recognize that protein synthesis on ribosomes bound to the rough endoplasmic reticulum occurs in the cytoplasm and ER, not mitochondria.
5. Conclude that oxidative phosphorylation, which includes the electron transport chain and ATP synthesis, is the primary process that takes place in mitochondria.