Homework SourseDuring photosynthesis the ratio of starch production to sucr
During photosynthesis, the ratio of starch production to sucrose production is determined by
The rate of malate diffusion between mesophyll and bundle sheath cells
Triose-P / Pi antiport across the chloroplast inner membrane
The rate of sucrose photorespiration in the mitochondria
NADPH and ATP production during the light reactions
The amount of malate accumulated in the vacuole
| The rate of malate diffusion between mesophyll and bundle sheath cells | ||
| Triose-P / Pi antiport across the chloroplast inner membrane | ||
| The rate of sucrose photorespiration in the mitochondria | ||
| NADPH and ATP production during the light reactions | ||
| The amount of malate accumulated in the vacuole |
Solution
During photosynthesis light reactions take place in grana of chloroplast and dark reactions take place in stroma of chloroplast. Three molcules of CO2 are fixed into one triose phosphate and 9 ATP, 6 NADPH are provided by the light-dependent reactions of photosynthesis. An antiporter in the inner chloroplast membrane exchanges Pi in the cytosol for 3-phosphoglycerate or dihydroxyacetone phosphate produced by CO2 assimilation in the stroma. Therefore, the ratio of starch production to sucrose production is determined by Triose-P / Pi antiport across the chloroplast inner membrane. Option 2 is correct.
