When conditions become unfavorable, plants cannot simply get up and move like we can. So the Creator God designed plants with the amazing ability to monitor their surroundings and respond appropriately. We call this involuntary movement a tropism. Plants have the marvelous ability to bend or redirect growth either toward a stimulus (a positive tropism) or away from it (a negative tropism). Plants direct their growth in response to several external conditions, but the three most common are gravity, sunlight, and touch.
Geotropism, also known as gravitropism, is a response to the earth’s gravity. When a seed begins to grow, the roots need to grow downward toward gravity, while the shoots need to grow upward away from gravity. Special cells in the tips of roots (called statocytes) are able to sense gravity. How is this done?
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