Essay Archive - Photoperiodism
Photoperiodism
Plants and animals in the temperate zones respond in different ways to
the amount of daylight in 24-hour periods. This response to day length is
called photo periodism. It controls many activities, among them is the
flowering of plants. The ability to respond to day length is linked to an
inner, light-sensitive circadian rhythm.
In the temperate zones, day lengths during the natural 24-hour cycle
vary with the seasons. In winter and spring, the period of light
lengthens; in summer and autumn, it shortens. Plants in these zones
undergo alternate 12-hour phases of li....
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