Final answer:
In the Calvin cycle, high-energy phosphate groups are donated by ATP to convert 3-phosphoglycerate to 1,3-bisphosphoglycerate. The enzyme phosphoglycerate kinase facilitates this energy transfer, which is essential for the synthesis of sugars.
Step-by-step explanation:
In the Calvin cycle, high energy phosphate groups are donated by ATP during the reduction phase. ATP provides the energy that is needed to convert 3-phosphoglycerate into 1,3-bisphosphoglycerate through a phosphorylation reaction. This step is vital for the biosynthesis of sugars in the Calvin cycle.
The ATP used in this process is produced in the light-dependent reactions of photosynthesis where sunlight is converted into chemical energy stored in ATP and NADPH. ATP is known as the energy currency of the cell, and it is used in various biological processes, including the Calvin cycle, to donate energy. Its high-energy phosphate bonds are critical for energy transfer within cells.
During these reactions, the enzyme phosphoglycerate kinase catalyzes the transfer of a phosphate group from ATP to 3-phosphoglycerate, forming 1,3-bisphosphoglycerate, which is a molecule with high-energy phosphate bonds. This is a critical step where energy from ATP is used to drive the endergonic (energy-consuming) reactions of the Calvin cycle, leading to the synthesis of glucose and other carbohydrates that are essential for plant growth and development.