Question

PLEASE ANSWER BOTH

1. What specific role would gas vesicles play in a cell's ability to oxygenically photosynthesize? Explain what specific part of photosynthesis is influenced by the presence of gas vesicles.

2. Why is the reverse TCA cycle considered anabolic, while the forward version of the TCA cycle is considered catabolic? Explain and provide examples.

Answer 1

Gas vesicles are majorly found in aquatic organisms. These vesicles are impermeable to water, but it is heavily permeable to gases and is always filled with air. They are used to control the cell's buoyancy and modify the cell's position in the water environment so it can be optimally located for photosynthesis and move to locations where availability of oxygen is sufficient. Gas vesicle induced buoyancy allows the movement of photosynthetic cyanobacteria into water column positions, allowing exposure to light that can support photography. The gas vesicles are involved in the first part of photosynthesis called light dependant reaction.