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A Plant's Response to Gravity

According to the statolith hypothesis the cells farther away from the earth elongate while those near the earth do not. true or false and why?

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As with many hypotheses the answer is it depends on whether you accept the hypothesis and whether there are other competing, more recent, more acceptable hypotheses.

The statolith hypothesis has distant roots (if you pardon the pun) as the idea that plants rerspond to gravity was first suggested in 1886 and 1892. The prestigious scientist Charles Darwin published twice on the subject both in 1903 and 1904.

More recent studies (1997) have suggested that the chain of events initiated by the descent of statoliths through the cytoplasm is not critical for gravity sensing of higher plants.

I have outlined the answer further on the attached file.

Good Luck.

Starch Statolith Hypothesis
How is it that plant roots can detect gravity? Root tips seem to be essential as if they are removed geotropism does not take place, however putting them back returns the geotropism. The central region of the root tip is called the columella. Cells there are rich in starch-containing organelles called amyloplasts or ...

Solution Summary

This is an interesting account of how a theory can be used to explain a basic phenomenon, why do plants roots grow downwards.