What is the action spectrum of photo peridism

Options

A. 430 and 660 nm
B. 640 and 660 nm
C. 660 and 730 nm
D. 700 and 900 nm

Answer

C

Explanation

Photoperiodic stimulus is believed to be perceived by Phytochrome. It is a blue-green pigment existing in two inter-convertible forms. `P_(fr) or P_(730)` (absorbs far-red light) and `P_(r) or P_(660)` (absorbs red light).