ANIMAL PHYSIOLOGY
NERVOUS SYSTEM
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
response of an organism to seasonal changes in day length.
|
|
|
directional movement of plant to directional stimulus.
|
|
|
non-directional movement of plant. The direction is determined by plant
|
|
|
response of plant to the touching
|
Detailed explanation-1: -The non-directive growth movements of plants, wherein the direction of stimulus is not the determinant of the direction of movement, are known as nastic movements. These movements always occur in one direction. Examples: Seismonasty, photonasty, thermonasty etc.
Detailed explanation-2: -Non-directional movement of plants in response to external stimuli is called nastic movement. Q. The movement or growth of any part of a plant in response to an external stimulus is called tropism or tropic movement.
Detailed explanation-3: -●The movement of the plant part in response to an external stimulus in which the direction of movement is not determined by the direction of stimulus is defined as the nastic movement. ● The folding up of leaves belonging to a sensitive plant such as Mimosa pudica is an example of nastic movement.
Detailed explanation-4: -Nastic movements are non-directional responses to stimuli (e.g. temperature, humidity, light irradiance), and are usually associated with plants. The movement can be due to changes in turgor.
Detailed explanation-5: -When the movement of a plant is dependent on the direction of stimulus, it is called directional movement. For example, shoot tip grows towards the source of light. When the movement of a plant is independent of the direction of stimulus, it is called non directional movement.