When the leaves of a sensitive plant are touched with a finger, they fold up and when the light fades at dusk, the petals of a dandelion flower close.

(a) State one way in which the above two processes are similar.

(b) State two ways in which the above two processes differ.

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Solution

(a) Both the processes are similar as the response is not determined by the direction of the stimulus. They are nastic movement.
(b) The first process of folding up of the leaf is thigmonastic and the stimulus is touch. The second process of closing of petals is photonastic and the stimulus is light.

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Similar questions

There are three plants A, B and C. The flowers of plant A open their petals in bright light during the day but close them when it gets dark at night. On the other hand, the flowers of plant B open their petals at night but close them during the day when there is bright light. The leaves of plant C fold up and drooop when touched with fingers or any other solid object.

(a) Name the phenomenon shown by the flowers of (i) plant A, and (ii) plant B.

(b) Name one flower each which behaves like the flower of (i) plant A, and (ii) plant B.

(d) Name a plant whose leaves behave like those of plant C.

(e) Which plant / plants exhibit the phenomenon based on growth movements?

Why is the folding up of the leaves of a sensitive plant on touching with a finger, not a tropism?

Q. Why is the folding up of the leaves of a sensitive plant on touching with a finger not a tropism?

Q. When the leaves of a Mimosa pudica plant are touched with a finger, they fold up quickly. This is an example of :
(a) chemotropism
(b) thigmonasty
(c) photonasty
(d) thigmotropism

Q. Which of the following are not tropisms?
(i) growing of pollen tube in response to a sugary substance
(ii) folding up of leaves of sensitive plant in response to touch
(iii) winding of tendril around a support in response to touch
(iv) opening up of the leaves of a daisy flower in response to light
(a) (i) and (ii) (b) (ii) and (iii) (c) (i) and (iv) (d) (ii) and (iv)

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When the leaves of a sensitive plant are touched with a finger, they fold up and when the light fades at dusk, the petals of a dandelion flower close. (a) State one way in which the above two processes are similar. (b) State two ways in which the above two processes differ.

When the leaves of a sensitive plant are touched with a finger, they fold up and when the light fades at dusk, the petals of a dandelion flower close.

(a) State one way in which the above two processes are similar.

(b) State two ways in which the above two processes differ.