Question

On touching, the leaves of Mimosa pudica droop down because of
A. Seismonasty
B. Nyctinasty
C. Chemonasty
D. Thigmotropism

Answer 1

Hint: Sensitive plant (Mimosa pudica), also referred to as a humble plant, is a plant in the pea family ( Fabaceae) that responds to contact and other stimuli by rapidly closing its leaves and drooping.

Complete Answer:
- The herb, native to South and Central America, is a widespread weed in tropical regions and has naturalised in warm areas elsewhere. It's usually grown as a curiosity in the greenhouses.
- The plant is a spiny subshrub and grows to around 30 cm (1 foot) tall. It has compound leaves and thin, globular, pink or mauve flower buds. The unusual rapid reaction of the plant to the touch is due to the rapid release of water from specialised cells located at the base of leaflets and leaf stalks.
- The leaves will be reopened in a few minutes, and it is thought that this adaptation is a protection against the browsing of herbivores who may be frightened by the movement. I
In addition to its response to physical stimuli, the leaves often droop in response to darkness and re-open with daylight, a process known as nyctinastic movement.
- Mimosa pudica is sort of like a natural pharmacy in a single herb. This fern-like plant has a long history of use in Ayurveda, a holistic healing method that originated in ancient India.
Ayurvedic practitioners used Mimosa pudica for head-to-toe diseases, such as mood disorders and wound healing.
- Thigmonasty or seismonasty is the nastic reaction of a plant or a fungus to a touch or vibration.
- Thigmotropism is the lateral response of a plant organ to a touch or physical contact with a solid object.
- Chemonasty is the nastic movement of a plant in response to a chemical stimulus.

Thus the correct answer is option(B) Nyctinasty.

Note: Mimosa Pudica has many benefits like
- Powerful Gut Scrubber
- Helps in Mental Health
- Kills Parasites
- Rich in Antioxidants