Which process is common to both cellular respiration and the light reactions of photosynthesis?

• A. Glycolysis
• B. Electron transport chain
• C. Krebs cycle
• D. Calvin cycle

Answer: (B)

Verified step by step guidance

1. Begin by understanding the processes involved in cellular respiration and photosynthesis. Cellular respiration includes glycolysis, the Krebs cycle, and the electron transport chain. Photosynthesis consists of light reactions and the Calvin cycle.
2. Identify the key components of the electron transport chain. In both cellular respiration and photosynthesis, the electron transport chain is a series of protein complexes located in the membrane that transfer electrons through redox reactions.
3. Recognize the role of the electron transport chain in energy production. In cellular respiration, it is located in the inner mitochondrial membrane, while in photosynthesis, it is found in the thylakoid membrane of chloroplasts.
4. Understand the function of the electron transport chain in generating ATP. In both processes, the electron transport chain creates a proton gradient that drives ATP synthesis through chemiosmosis.
5. Conclude that the electron transport chain is the common process between cellular respiration and the light reactions of photosynthesis, as it is integral to energy conversion in both pathways.