Plants recycle carbon during photosynthesis through a process called carbon fixation. Here is a step-by-step explanation of how this process occurs:
1. Carbon dioxide (CO2) is obtained by plants from the atmosphere through small openings called stomata present on their leaves.
2. Inside the leaves, CO2 enters the cells where chloroplasts are located.
3. Chloroplasts contain a pigment called chlorophyll, which absorbs light energy from the sun.
4. This absorbed light energy powers a chemical reaction in the chloroplasts known as the light-dependent reactions, which generate adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH).
5. ATP and NADPH, along with the carbon dioxide obtained earlier, are then used in the light-independent reactions, also known as the Calvin cycle or the dark reactions.
6. During the Calvin cycle, CO2 is transformed and combined with a molecule called ribulose-1,5-bisphosphate (RuBP) to form a three-carbon compound called 3-phosphoglycerate (3-PGA).
7. Some of the ATP produced in the light-dependent reactions is utilized to convert 3-PGA into glyceraldehyde 3-phosphate (G3P).
8. G3P can be further converted into various organic compounds needed by the plant, such as glucose, cellulose, starch, or plant proteins.
9. Some G3P molecules are used in the regeneration of RuBP, which is important for continued carbon fixation to take place.
10. During this process, oxygen is also released as a byproduct.
By recycling carbon dioxide and incorporating it into organic compounds, plants remove CO2 from the atmosphere, reducing greenhouse gas levels and playing a critical role in mitigating climate change.
How do plants recycle carbon during photosynthesis?
1 answer