Question

What is oxidized and reduced in photosynthesis and cellular respiration?

Answer 1

Oxidation and reduction in photosynthesis and cellular respiration:

1. Cellular respiration is an oxidative process that produces carbon dioxide, water, and energy by oxidizing an electron donor and reducing oxygen.
2. Carbon dioxide, which is lowered during photosynthesis, appears to accumulate electrons, which is paradoxical.
3. The influx of negatively charged electrons reduces the total charge of the molecule, making it less positive and more negative. This electron transfer is called reduction.
4. Two substrates (carbon dioxide and water) react in the presence of light to produce two products during photosynthesis (carbohydrates and oxygen).
5. Water is oxidized to liberate oxygen in the presence of light (photolysis), whereas carbon dioxide is reduced to carbohydrates in the dark utilizing energy trapped during the light reaction.
6. During photosynthesis, CO₂ is reduced to glucose, and H₂O is oxidized to release O₂.
7. In cellular respiration, glucose is oxidized, and oxygen is reduced to form CO₂ and water.