Question

When the plant Mimosa pudica is touched it begins to fold up and droop. The types of movement it shows are given below. Select the correct option.
(i) Seismonastic movement (ii) Nyctinastic movement
(iii) Thigmonastic movement (iv) Chemonastic movement

• A. (i) and (iii)
• B. (iii) and (iv)
• C. (ii) and (iii)
• D. Only (i)

Answer 1

The correct option is D Only (i)

Seismonastic movement is a response to touch or blow. In Mimosa pudica plant, turgor movement is seen in leaflets in response to touch. When it is touched, it begins to fold up and droop. Nyctinastic movement is the response of a plant in response to darkness. In this, plant shows circadian rhythm that function on a 24 hour clock. It is seen in leaves of many legume plants. Thigmonastic movement is the response of a plant to touch or vibration. In Drosera, tentacles bend towards the insect's direction after coming in contact. Chemonastic movement is the response of a plant to chemical stimulus. An example is growth of pollen tube towards embryo sac due to presence of sugar in the style.

Thus, the correct answer is option D.