Action spectrum of photosynthesis Fig 39 3 Fig


























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Action spectrum of photosynthesis Fig 39. 3
Fig 39. 12 Seedling germination may depend on light
Fig 39. 15 Phytochrome: a reversible receptor
http: //www. mcdb. ucla. edu/Research/Tobin/research. html
Hey, want to swap some pollen?
I don’t have any flowers.
I guess I will have to find another plant.
I hate when that happens. You give really good pollen.
Plants use day length to synchronize flowering Fig 39. 13
The critical period is actually night length Fig 39. 13
Phytochrome regulates flowering time Fig 39. 14
Plants use night length to determine the season.
What about daily time. . . the circadian clock
Circadian Rhythms: daily patterns set by light (northern flying squirrel)
Phytochrome sets the circadian clock http: //www. mcdb. ucla. edu/Research/Tobin/research. html http: //plantsinmotion. bio. indiana. edu/plantmotion/movements/leafmovements/clocks. html (oxalis) http: //plantsinmotion. bio. indiana. edu/plantmotion/movements/tropisms. html (sunflower tracking)
The molecular identity of the circadian clock is unknown http: //www. ou. edu/wanglab/Circadian. html
CCA 1 is a transcription factor that regulates some photosynthetic genes. 25 28 31 34 37 40 43 46 49 52 55 57 http: //www. mcdb. ucla. edu/Research/Tobin/research. html
Overexpression of CCA 1 in transgenic Arabidopsis plants abolished the circadian rhythms of several genes with dramatically different phases. http: //www. mcdb. ucla. edu /Research/Tobin/research. html
Plants were created that lack a functional CCA 1 gene http: //www. mcdb. u cla. edu/Research/T obin/research. html
With no CCA 1 protein, phytochrome induction of Lhcb RNA is reduced to 60% of the normal level. http: //www. mcdb. ucl a. edu/Research/Tobin /research. html
http: //www. mcdb. ucla. edu/Research/Tobin/research. html
http: //www. mcdb. ucla. edu/Research/Tobin/research. html
Plants overexpressing CCA 1 had delayed flowering. Furthermore, leaf movement rhythms were abolished
CCA 1 is part of the oscillator, but it is not THE oscillator/clock. http: //www. ou. edu/wanglab/Circadian. html
Enjoy your break. . .