A plant is exposed to a toxin that blocks ABA receptor sites in the plasma membrane. What is the likely consequence of this exposure?
A. The plant will lose excess water through transpiration and suffer dehydration.
B. ABA will enter the cells by an alternative route and normal function will be restored.
C. Oxygen deprivation will trigger the release of ethylene, which will in turn suppress root growth.
D. Gibberellin production will increase, allowing the plant to access more nutrients in the soil.
E. The guard cells will become flaccid and gas exchange will cease.
Answer: A
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