phototropism
Quick Summary
Phototropism is a plant's directional growth in response to light. This response is primarily mediated by a plant hormone called auxin. Auxin is produced in the tip of the plant's shoot and moves downward. When light shines from one direction, auxin accumulates on the shaded side of the stem, causing those cells to elongate more than the cells on the illuminated side. This differential growth results in the stem bending towards the light source, which is beneficial for photosynthesis. This phenomenon is a type of tropism, which is a plant's oriented response to a stimulus.123
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auxin…stems toward the light (phototropism) and against the force of gravity (geotropism). The phototropic response occurs because greater quantities of auxin are distributed to the side away from the light than to the side toward it, causing the shaded side to elongate more strongly and thus curve the stem…
Read More…stems toward the light (phototropism) and against the force of gravity (geotropism). The phototropic response occurs because greater quantities of auxin are distributed to the side away from the light than to the side toward it, causing the shaded side to elongate more strongly and thus curve the stem…
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angiospermTransport and plant growth…auxin distributions are responsible for phototropic responses—i.e., the growth of plant parts such as shoot tips and leaves toward light. In certain cases auxin may be destroyed on the illuminated side, and the unilluminated side with more auxin elongates, causing the shoot to bend toward the light.
Read More…auxin distributions are responsible for phototropic responses—i.e., the growth of plant parts such as shoot tips and leaves toward light. In certain cases auxin may be destroyed on the illuminated side, and the unilluminated side with more auxin elongates, causing the shoot to bend toward the light.
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hormoneAuxins…stems toward the light (phototropism) and against the force of gravity (geotropism). The phototropic response occurs because greater quantities of auxin are distributed to the side away from the light than to the side toward it; the geotropic response occurs because more auxin accumulates along the lower side of…
Read More…stems toward the light (phototropism) and against the force of gravity (geotropism). The phototropic response occurs because greater quantities of auxin are distributed to the side away from the light than to the side toward it; the geotropic response occurs because more auxin accumulates along the lower side of…
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