1) After Thanksgiving break you return to the HTHMA garden to find that your crops have not been watered in over two weeks. Most of your plants are dead and those that are alive are barely hanging on. In relation to the process of photosynthesis, describe what has happened to your plants.
Water is a reactant in photosynthesis. Without it, the photosynthetic systems in the plant's chloroplasts cannot synthesize glucose. The significant lack of H2O starved the plants of energy.
2) Upon microscopic inspection of the underside of your plant’s leaves, you notice that in an attempt to conserve water the stomata (aka stomates) are closed. Explain in detail how this impacts the light independent reactions of photosynthesis.
Since gas flow is regulated through the stomates, if the stomates close up then the plant can't absorb CO2 for the light independent stage of photosynthesis or release O2, the byproduct. This means that the plant can perform the light dependent stages of photosynthesis with the conserved water to create ATP, but cannot synthesize glucose because of the lack of CO2/O2 flow that the Calvin Cycle needs.
1) How is water used in PS?
ReplyDeleteWater donates electrons (oxidation) to electron carriers, which provide temporary energy in the photosystem that is necessary for other reactions to take place.
ReplyDelete