Question

When the dark period of short-day plants is interrupted by a brief exposure of light, then the plant
A. Flowering will be delayed
B. Flower immediately
C. Give more flowers
D. Turn into a long day plant

Answer 1

Short- day plants are the plants which require low sunlight and photosynthesis is less done. They stand in sunlight for a shorter duration of time. Firstly, lets understand why desert plants take carbon dioxide, because of very hot temperature, plants tend to lose water which is called transpiration due to which in the morning they do not take carbon dioxide. As in the night the temperature is very low so that is why the stomata of desert plants or cactus opens at night so that the water percent in the plant could not get out of the plant.

Complete answer:
Option A: Flowering will be delayed- as short-day plants show inflorescence during night time. As they possess flowering during night time in the dark period, hence more exposure to sunlight will disrupt the mechanism and flowering will be delayed.
Option A is the correct answer.
Option B: Flower immediately- plants which require more time for darkness or flowers in the dark time that is night time is called as short-day plants. Short plants require darkness for flowering hence it cannot flower immediately.
Option B is not the correct answer.
Option B Give more flowers- inflorescence has nothing to do with a greater number of flowers, it does not matter if the plants get exposed to high time of sunlight it cannot possess flowering only.
Option C is not the correct answer.
Option D: Turn into a long day plant- long day plants require more sunlight and they show flowering in day time only.
Option D is not the correct answer.

Hence, Option A is the correct answer.

Note:
Short-day plants and long-day plants are described under photoperiodism. Photoperiodism is the concept where plants are described on the basis of exposure to sunlight. They perform all their activities according to the exposure of sunlight such as short-day plants or also known as night time plants perform photosynthesis at night.