International A Level Biology / Coordination in animals and plants

Phytochrome and flowering revision notes

Edexcel International A Level Biology (YBI11), chapter 24: Coordination in animals and plants, specification point 8.11. Part of the full course.

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Phytochrome is a light-sensitive pigment that switches between two forms. Plants use the amount of its active form at dawn to measure the unbroken night and time flowering.

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