Page 89 - Teknik Menjawab Soalan PSPM Biologi

Role of phytochromes in controlling

flowering

∙ Phytochrome is the main photoreceptor

for photoperiodism.

∙ Exists in two interconvertible forms (P R

and P FR)

∙ P inactive form while P FR is the active
R
form

∙ Plant synthesizes phytochrome in its

inactive form P R

∙ During the day, P absorbs the red light
R
and changes rapidly to P .
FR

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