question_answer

 The pigment sensitive for red and far-red light is:

A)  chlorophyll    

B)  phytochrome

C)  cytochrome    

D)  carotene

Correct Answer: B

Solution :

 'Phytochrome' is a chromoprotein or protein pigment involved in many aspects of morphogenesis.  It was discovered by Borthwick and others in 1952. It was isolated from etiolated maize seedlings by Butler et.al. in 1959. Phytochrome exists in two states\[-{{\text{P}}_{\text{r}}}\] or \[{{\text{P}}_{\text{660}}}\text{,}\]associated with cytoplasm and \[{{\text{P}}_{\text{fr}}}\]or \[{{\text{P}}_{730}}\]which is membrane associated. Chlorophyll is a green pigment involved in capturing the light energy that drives photosynthesis. It is found in plants, algae and cyanobacteria. Five types of chlorophylls occur in plants other than bacteria-a, b, c, d and e. Chlorophyll-a is universal photosynthetic pigment, present in all photosynthetic. Cytochrome    is    heme    containing electron-transport intermediates in which the iron undergoes valency changes during electron transfer. Carotene is a red orange or yellow pigment, precursor of vitamin-A.