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Name: Eric
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Question:
Does Gravity effect the direction in which a plant grows?



Replies:
Eric,

Yes, plants do respond gravity. Living things that are sensitive to gravity are said to be geotropic. Plant stems are negatively geotropic and the roots are positively geotropic. Some scientists think this tropism is caused by plant growth hormones known as auxins. Auxins can speed up or slow down the growth of certain areas of a plant. If a plant stem falls and continues growing it is thought that the stem bends upward when auxins are pulled to the bottom side of the stem by gravity. The bottom side then grows faster than the top side which causes it to bend upward. As the stem becomes upright again the auxins even out and the stem then grows straight. Sounds confusing, doesn't it! Most general botany books have information which may be clearer than my account. General botany books may be found in most libraries. Good luck?

Wayne Vanderploeg


Yes. Plants grow against the pull of gravity.

Richard Barrans Jr., Ph.D.


I am not a plant type, but check the word geotropism. It is the effect of gravity on plants.

Dr. Myron


Most plants have a negative reaction to gravity, that is they grow opposite the pull of gravity in order to get up above the soil. J. Elliott


Yes, but it depends on which part of the plant you are asking about. Roots are programmed to grow toward gravity (they are positively gravitropic) and stems grow away from gravity (negatively gravitropic). Even if you turn the plant sideways, it will "know" where it is in space.

Kathy Van Hoeck



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