Question

Does C₄ photosynthesis occur at night?

Answer 1

C₄ photosynthesis:

1. C₄ carbon fixation, also known as the Hatch-Slack pathway, is one of three known photosynthetic carbon fixation pathways in plants.
2. It is found in chloroplasts.
3. Hatch and Slack, two Australian scientists, found it.
4. Carbon dioxide is concentrated in bundle sheath cells around Rubisco during C₄ photosynthesis, which produces a four-carbon molecule.
5. RuBisCO's primary function is photosynthesis and photorespiration.
6. It catalyzes the first step in the C3 pathway or Calvin cycle, namely the carboxylation of RuBP.
7. It results in the production of two 3-PGA molecules.
8. The enzyme ribulose 1,5-bisphosphate carboxylase (Rubisco) catalyses carbon dioxide entrance into photosynthetic metabolism, provides acceptor molecules that consume the products of photosynthesis's light processes, and regulates the pool sizes of critical photosynthetic intermediates.
9. RuBisCo is an enzyme that catalyses carboxylation (the chemical process by which a carboxyl group -COOH is added) of ribulose-1,5-bisphosphate, RuBP, a 5-carbon molecule, by carbon dioxide (a total of 6 carbons) in a two-step reaction.
10. They store it as 4 carbon molecules, releasing carbon dioxide during daylight when photosynthesis's light-dependent activities can occur.
11. This arrangement distributes carbon dioxide directly to Rubisco, effectively eliminating oxygen interaction and the necessity for photorespiration.
12. CAM is a C₄ plant that fixes CO₂ throughout the night.
13. C₄ photosynthesis does not take place at night.