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Old 01-13-2006, 03:16 PM
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dreamerofeternity would have made Einstein proud! dreamerofeternity would have made Einstein proud!

Phototropism (and every other "tropism" ex. geotropism in roots) is caused by plant hormones. Check those out. A few well-known plant hormones include auxins, cytokinins, and gibberellins. Most of these are growth hormones. For example, gibberellin is the hormone that increases the stem growth, but stumps the leaf growth. Depending on which side of the plant has more hormones, it will cause an uneven growth towards the other side, and therefore, the plant bends towards light.

here's a site that has a little on each of the common plant hormones:

Don't worry if the scientific jargon stumps you. Keep on posting on this thread, and I'll come back to answer questions. For every science project, you have to do research, and deciphering research is just as hard as the experiment. But once you finish, everything makes sense, and it becomes a lot easier.

Also, connecting to your experiment, you want to see if there are any effects of the color of the light on plant hormones. Is there more phototropism when I use yellow light than blue light?

I wish you good luck!
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