You wish to test the hypothesis that the gravitropic response is stronger than the phototropic response in stems. How could this hypothesis be tested and what results would be predicted?
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Gibberellins are responsible for cell elongation between nodes of a stem. Miniature, or dwarf, varieties of plants have short internode cells. Remembering that a hormone only works after it binds to a receptor protein, propose at least two different hypotheses that could explain why a plant would lack a hormonal response.
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