Vernalisation is done at

The effect of the length of day (light duration) on flowering is called:

$A$ hypothetical chemical involved in the flowering of plants is:

$A$ 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 stimulus for flowering is perceived by which part of the plant?

Which of the following is a long day plant?