Question

Fill in the blank with the correct word.

Answer 1

Answer:

When a plant responds to changes in the length of day by flowering during certain seasons, it is called  photoperiodism .

To survive the cold winter months, some plants go into a state of growing

dormancy.

Explanation:

Answer 2

Answer:

photoperiodism

Explanation:

this determines the length and height of the plants when plants adjust to growth.Plants also use the phytochrome system to adjust growth according to the seasons. Photoperiodism is a biological response to the timing and duration of dark and light periods. Since unfiltered sunlight is rich in red light, but deficient in far-red light, at dawn, all the phytochrome molecules in a leaf convert to the active Pfr form and remain in that form until sunset. Since Pfr reverts to Pr during darkness, there will be no Pfr remaining at sunrise if the night is long (winter) and some Pfr remaining if the night is short (summer). The amount of Pfr present stimulates flowering, setting of winter buds, and vegetative growth according to the seasons.