Pls tell question 4

Dear Student,

a) Tendril is a thin thread-like growth on the stems or leaves of a climbing plant.
The two types of tendrils are stem tendrils and leaf tendrils.
X - Stem tendril and Y - leaf tendril

b) Tendrils grow towards a support in response to their touch. The tendrils intertwine around whatever it touches. In this way it helps the plants with the weak stems to climb.

c) The phenomenon is known as thigmotropismThigmotropism is a movement or growth of plant in response to touch or contact stimuli. It is easily visible in plant touch me not (Mimosa pudica). Another example of thigmotropism is the coiling of tendrils around a solid object towards the stimulus. Roots also depend on touch sensitivity to navigate their way through the soil but when a root "feels" an object, the root grows away from the object. 

(Note: The mechanism of thigmotropism is quite complex and you will read about it in higher classes.)

d) 
Stem tendril Leaf tendril
Stem tendrils are shoots that grow out of stem. Leaf tendrils are modified leaves that emerge from leaf node.
These are modified shoots. These may be modified leaves, leaflets, leaf tips, or leaf stipule
For example:  grapes For example: peas
 
e) Another example of a plant that shows thigmotropism - Mimosa pudica (Touch me not) (explanation given above).



Regards
 

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