Chrysanthemum flowers in the winter season or in the evening because it is a:

$A$ group of plants flowered when exposed to a $12$ hour day and $12$ hour night cycle. Another group of the same plants did not flower when exposed to the same day-night cycle but with a brief light interruption during the night. What type of plants are these?

The site of perception of light in plants during photoperiodism is:

Which of the following statements are $INCORRECT$ with respect to phytochrome?
$i$. Phytochrome is a light-receiving proteinaceous pigment present in the leaves of plants.
$ii$. Phytochrome pigment exists in two forms.
$iii$. Two forms of phytochromes are interconvertible.
$iv$. Phytochromes are located in the chloroplast of green cells.
$v$. Phytochrome $P_r$ form inhibits flowering in $LDP$ during the dark period.

Phytochrome is closely related to

Define/Explain: Vernalization.