Question

1. a plant closes its stomata during a drought. how does this impact a plants ability to perform photosynthesis? include which reactants and products are impacted and why.

Explanation:

Stomata are pores on plant leaves. They take in \(CO_2\) (a reactant for photosynthesis) and release \(O_2\) (a product). When stomata close during drought:

• Reactant \(CO_2\) intake is reduced. Photosynthesis equation: \(6CO_2 + 6H_2O

ightarrow C_6H_{12}O_6+6O_2\). Less \(CO_2\) means less raw material for the Calvin cycle (light - independent reactions).

• Product \(O_2\) release is also affected. Since \(O_2\) is a by - product of the light reactions (where \(H_2O\) is split), and the overall photosynthetic rate slows (due to lack of \(CO_2\) for the subsequent Calvin cycle), less \(O_2\) will be produced and released. Also, water loss (transpiration) is reduced, but in terms of photosynthesis, the gas exchange ( \(CO_2\) in, \(O_2\) out) is disrupted.

Answer:

Closing stomata during drought reduces \(CO_2\) (reactant) intake for photosynthesis (as \(CO_2\) enters through stomata) and also affects \(O_2\) (product) release (since the overall photosynthetic process slows, less \(O_2\) is produced). The reaction \(6CO_2 + 6H_2O
ightarrow C_6H_{12}O_6 + 6O_2\) is hindered as \(CO_2\) is limited, and thus the production of glucose (\(C_6H_{12}O_6\)) and \(O_2\) is reduced.