Question

There are three plants A, B and C. The flowers of plant A open their petals in bright light during the day but close them when it gets dark at night. On the other hand, the flowers of plant B open their petals at night but close them during the day when there is bright light. The leaves of plant C fold up and droop when touched with fingers or any other solid object.

1. Name the phenomenon shown by the flowers of (i) plant A and (ii) plant B.
2. Name one flower each which behaves like the flower of (i) plant A and (ii) plant B.
3. Name the phenomenon exhibited by the leaves of plant C.
4. Name a plant whose leaves behave like those of plant C.
5. Which plant/plants exhibit the phenomenon based on growth movements?

Answer 1

1. The phenomenon shown by the flowers of plants A and B is photonasty.
2. A flower which behaves like the flower of
   1. plant A is a dandelion and
   2. plant B is a moonflower.
3. The leaves of plant C exhibit thigmonasty.
4. A plant whose leaves behave like those of plant C is Mimosa pudica.
5. Plants A and B exhibit the phenomenon based on growth movements.