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Question
The height of a plant is regulated by ______.
Options
DNA is directly influenced by growth hormones.
Genes which regulate the proteins directly.
Growth hormones are under the influence of the enzymes coded by a gene.
Growth hormones are directly under the influence of a gene.
Solution
The height of a plant is regulated by Growth hormones under the influence of the enzymes coded by a gene.
Explanation:
Under the control of the enzymes that the gene codes for, growth hormones control the plant's height. The amount of growth hormones a plant produces is dependent on the effectiveness of the relevant enzyme. Effective enzymes generate more of the hormone, which causes the plant to grow taller. However, if the enzymes are less effective, less hormone is released, which causes the plant to become stunted.
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