Short/Long day plants

Question 1

Photoperiodism

Answer 1

The response of an organism to changes in day length.

Question 2

Critical Night Length

Answer 2

Every plant has a critical night length, and depending on whether the plant is a short-day plant (SDP) or a long-day plant (LDP), a night length over or under critical night length will cause this plant to flower or to not flower.

Question 3

Long-day Plants

Answer 3

A long-day plant is a plant that flowers when the noctoperiod is less than its critical night length.

Question 4

Short-day Plants

Answer 4

A short-day plant is a plant that flowers when the noctoperiod is more than its critical night length.

Question 5

Day Neutral Plants

Answer 5

A plant where flowering can occur irrespective of day length.

Question 6

Pigment

Answer 6

Substances produced by living organisms that have a colour resulting from selective colour absorption.

Question 7

Phytochrome

Answer 7

Plants recognize the changing night lengths using phytochromes. During the day phytochromes in the Pr form, absorb red light from the sun and become Pfr (inhibits flowering in SDP and promotes flowering in LDP. In the night Pfr absorbs infrared light and becomes Pfr again.