Question
Biology Question on plant growth and development
Phytochrome becomes active in
A
red light
B
green light
C
blue light
D
none of these.
Answer
none of these.
Explanation
Solution
Phytochrome is a bright blue or bluish green pigment which was first of all isolated from plasma membrane of alga Mougeotias. It is a photoreceptive j pigment. Phytochrome has a light absorbing or light detecting portion (the chromophore) attached to small protein of about 1,24,000 daltons. Phytochrome occurs in 2 forms, i.e., PR and Pf.R (i.e., red light and far red light absorbing forms) and these 2 forms are interconvertible. 1 It is involved in the perception of photoperiodic stimuli controlling flowering and other morphogenetic | phenomenon in plants.