Photosynthesis Question 38

38. The wavelength of light absorbed by $Pr$ form of phytochrome is

(a) $680 nm$

(b) $720 nm$

(c) $620 nm$

(d) $640 nm$

Show Answer

Answer : a

Hints & Solution

(a) The Pr form absorbs light between 660 to $680 nm$ and absorbs at a peak of $666 nm$. It is the form synthesized in dark-grown seedlings. When Pr absorbs red light, it is converted to the Pfr form.