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Answer 4 questions correctly in a row.

The following passage describes the effects of a gene mutation, which is a permanent change in a gene. Read the passage and then follow the instructions below.

pea plants with different amounts of gibberellin

A pea plant's height is affected by substances that are made inside the plant's cells. One of these substances is called gibberellin.
Gibberellin is made in a pea plant's cells by a protein called GA 3-oxidase. The GA 3-oxidase protein is encoded by the LH gene.
A certain pea plant had a mutation in its LH gene. Compared to the LH gene without a mutation, the mutated LH gene encoded a form of the GA 3-oxidase protein with a different structure.
This different form of the GA 3-oxidase protein could make only a small amount of gibberellin. The plant with the mutation grew to a shorter height than pea plants containing more gibberellin.