Question
Discuss about discovery of phytochromes.
✓
Answer
$1.$ Phytochromes are proteinaceous pigments present in cell membrane of green cells.
$2.$ Phytochromes receive photoperiodic stimulus and induce flowering in plants in response to light duration.
$3.$ Hendrick and Borthwick observed that in $\text{SD}$ plants flowering is inhibited if dark period is interrupted by flash of red light $(660 \ nm).$
$4.$ If flash of far red light $(730 \ nm)$ is given then again flowering is observed in $\text{SD}$ plants.
$5.$ Pigment system of plant receives photoperiodic stimulus and these pigments exist in two interconvertible forms $P^{fr}$ and $P^r$
$2.$ Phytochromes receive photoperiodic stimulus and induce flowering in plants in response to light duration.
$3.$ Hendrick and Borthwick observed that in $\text{SD}$ plants flowering is inhibited if dark period is interrupted by flash of red light $(660 \ nm).$
$4.$ If flash of far red light $(730 \ nm)$ is given then again flowering is observed in $\text{SD}$ plants.
$5.$ Pigment system of plant receives photoperiodic stimulus and these pigments exist in two interconvertible forms $P^{fr}$ and $P^r$
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