Tag: movement in plants

Thigmonastic movements occur in some plants in response to tactile stimuli. The movements may be defensive or offensive-response to the touch of an herbivore interested in ingesting the plant or by contrast, in response to the touch of an insect that may serve as a potential meal for a carnivorous plant.

Phototaxis - is a kind of taxis or locomotory movement, that occurs when a whole organism moves towards or away from stimulus of light. It is called positive if the movement is in the direction of increasing light intensity and negative if the direction is opposite
So, the correct answer is 'Phototaxis'

Bulliform cells are large, bubble-shaped epidermal cells present in the leaves of many grasses that lose water and cause the leaves to fold or roll during drought.

Stimulus for flowering will be accepted by young leaves. Apart from light and chemical stimulus for flowering, temperature is also one important stimulus that a lot of plant species use to flower, e.g., some orchid species.

Opening of a bud and drooping of bud are called as epinastic movements. It is well defined as the increased growth of the upper surface of a plant part, such as leaf, resulting in a downward bending of the part.

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.

The flowers of sunflower open in the morning which is an example of photonasty (regulated by light). Tulip flowers open at high temperature, example of thermonasty (regulated by temperature).

Nastic movements are responses of plant parts to stimuli. Epinasty is the downward bending of a leaf resulting from greater growth of the upper side than of the lower side. Due to more growth on the upper side, the flower will open due to epinasty. The hyponasty is an upward bending of leaves resulting from greater growth of the lower side. Nutation is the bending movements shown by some plant parts due to the unequal rate of growth of different parts of plants. Movement of plant in response to light is called as phototaxis.

Autonomic movement is the spontaneous movement of the protoplasm seen in aquatic plants due to internal stimulus. It is not related to the external stimulus. Movement of cilia and flagella is an example of autonomic movement. A movement shown by a plant part in response to an external factor is called as paratonic movement. In this, the direction of movement is controlled by the direction of the stimulus. Mechanical movements are seen by non-living organs of plants due to hygroscopic changes.