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Unformatted text preview: The red-sensitive photoreceptors are a group of pigments called phytochromes. Phytochrome was discovered in lettuce, a plant whose seeds only germinate when exposed to light. A USDA team in the 1930's exposed lettuce seeds to red light of 660 nm. (It was known that cocklebur flowered best when stimulated with red light of 669 nm and they thought the germination response might be similar.) 660 nm promoted the best germination in lettuce. However, if the 660nm exposure was followed by a flash of far-red light at 730 nm, seeds did not germinate....
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This note was uploaded on 01/08/2012 for the course BIO 213 taught by Professor Makina during the Fall '09 term at SUNY Stony Brook.
- Fall '09