gravitropism
Quick Summary
Gravitropism, also known as geotropism, is a plant's response to gravity. This means that plant parts will grow in a direction influenced by the pull of gravity. For example, a plant's roots will always grow downwards into the soil, regardless of how the seed is oriented.12
This growth response is regulated by plant hormones, primarily auxins. Auxins promote lengthwise growth in plants. In response to gravity, auxins accumulate on the lower side of stems and roots. In stems, this causes the cells on the lower side to elongate more, making the stem bend upwards, away from gravity. In roots, however, a higher concentration of auxin inhibits growth, causing the roots to bend downwards, with gravity.34
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angiospermRoot systems…that grows vertically downward (positive geotropism). From the taproot are produced smaller lateral roots (secondary roots) that grow horizontally or diagonally. These secondary roots further produce their own smaller lateral roots (tertiary roots). Thus, many orders of roots of descending size are produced from a single prominent root, the taproot.…
Read More…that grows vertically downward (positive geotropism). From the taproot are produced smaller lateral roots (secondary roots) that grow horizontally or diagonally. These secondary roots further produce their own smaller lateral roots (tertiary roots). Thus, many orders of roots of descending size are produced from a single prominent root, the taproot.…
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Responses to gravity and light are also under auxin control. Auxins move to the lower side of a leaning stem; cells on the lower side then elongate and cause the stem to bend back to a vertical position. Response to gravity in many roots is the opposite…
Read MoreResponses to gravity and light are also under auxin control. Auxins move to the lower side of a leaning stem; cells on the lower side then elongate and cause the stem to bend back to a vertical position. Response to gravity in many roots is the opposite…
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auxin…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 toward the light. Similarly, the geotropic response…
Read More…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 toward the light. Similarly, the geotropic response…
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hormoneAuxins…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 the coleoptile than along the upper side.…
Read More…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 the coleoptile than along the upper side.…
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