NEET BIOLOGY

Detailed explanation-1: -In response to touch, the leaves of this plant shift rapidly. This movement does not involve any type of growth. This type of movement is known as seismonastic movement.

Detailed explanation-2: -Movement of leaves of touch-me-not plant is a nastic movement whereas growth of stem towards light is a tropic movement. The growth of stem is a direction based movement i.e. it grows towards the stimulus of light.

Detailed explanation-3: -The opening and closing of the plants’ leaflets and the entire leaf are controlled by fluid-filled sac-like structures found at the base of the compound leaf and each leaflet.

Detailed explanation-4: -Seismonasty or thigmonasty is the nastic movement induced in plants where the stimulus is touch. Touch-me-not plant, which has the scientific name as Mimosa pudica is sensitive to touch and is thus called as seismonastic.

Detailed explanation-5: -When we touch Mimosa pudica (touch me not ), our touch acts as a stimulus for the plant and it closes its leaves in return. Some chemicals are released from the stem when we touch the plant. These chemicals force water to move out of the cell leading to the loss of turgor pressure. As a result, leaves droop.