Tag: movement in plants

Thigmonasty or seismonasty is the nastic response of a plant or fungus to touch or vibration. Examples are many species in the leguminous subfamily, Mimosoideae, active carnivorous such as Dionaea and a wide range of pollination mechanisms.

External stimulus induces tropic, nastic and tactic movements.

1. Tropic movement - biological phenomenon indicating growth or turning movement of a plant, in response to an external stimuli.
2. Nastic movements - Non-directional responses in response to external stimulus
3. Tactic movements - It includes phototactic, chemotactic and thermotactic movements.
   

Nastic movements are non-directional movements in which direction of response or movement is determined by the structure of responsive region. Nastic movement for instance, could be due to changes in the turgor pressure.

Seismonasty is defined as the nastic movement in response to shock, especially rapid folding of te leaflets of the sensitive plant due to changes in turgor pressure caused by vibration. It is also called as thigmonasty, because the external stimuli is touch.

Photonasty - the tendency in certain plant species to respond to light by developing sufficient cellular force or growth on one side of an axis to change the form or position of the axis, as in the opening and closing of the flowers of four-o'-clocks.

Haptonasty or thigmonasty is the non-directional movement of a plant part in response to the touch of an object. The closing of the lamina of Venus fly trap is a type of haptonasty as a result of contact with an insect. If an insect happens to cross the lamina, the leaf will close quickly to prevent its escape. 

Nastic movements are responses of plant parts to stimuli. Photonastic movement is the nastic response of plant in response to light. Thermonastic movement is the a nastic response of plant in response to change in temperature. Seismonastic movement is the nastic response of a plant to touch or vibration. Dropping of leaves of Mimosa pudica upon touching is due to seismonasty. Thigmonastic movement is the nastic response of a plant to touch. The movements of tentacles of Drosera when comes in contact with insect is due to thigmonasty.

Nastic movements are responses of plant parts to stimuli. Seismonasty is the nastic response of a plant to touch or vibration. Dropping down of leaves of Mimosa pudica upon touching is due to seismonasty. Nyctinasty is the rhythmic nastic movement of plant in response to the onset of darkness. Chemonasty is the nastic response of a plant to external chemical. 

Nastic movement is the movement shown by plant part in response to environmental stimuli. This movement is repeatable and reversible. Examples include the folding of leaves of Mimosa pudica when touched. The folding and recoiling of leaves of Mimosa pudica in response to touch is called as thigmonastic movement.