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प्रश्न
How do auxins promote the growth of a tendril around a support?
उत्तर
When tendrils come in contact with any support, the part of the tendril in contact with the object does not grow as rapidly as the part of the tendril away from the object. This is caused by the action of auxin hormone. Less auxin occurs on the side of contact as compared to the free side as a result, auxin promotes growth on the free side and the tendrils coil around the support.
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संबंधित प्रश्न
What is the stimulus in phototropism?
What is the stimulus in thigmotropism?
Give the scientific terms used to represent the Growing of roots towards the earth.
Give the scientific terms used to represent the Bending of roots towards water.
What does a tendril do in response to the touch of a support? What is this phenomenon known as?
Plant shoot grows upward in response to ______.
Tendrils wind around a support in response to ______.
Define phototropism. Give one example of phototropism.
What is meant by positive tropism and negative tropism? Explain with examples.
Which of the following is not caused by a growth movement?
The root of a plant is :
(i) positively phototropic but negatively geotropic
(ii) positively geotropic but negatively phototropic
(iii) negatively phototropic but positively hydrotropic
(iv) negatively hydrotropic but positively phototropic
(a) (i) and (ii) (b) (ii) and (iii) (c) (iii) and (iv) (d) (i) and (
A growing seedling is kept in a dark room. A burning candle is placed near it for a few days. The top part of seedling bends towards the burning candle. This is an example of :
(a) chemotropism
(b) hydrotropism
(c) phototropism
(d) geotropism
A potted plant having straight parts A and B was placed horizontally on its side as shown in Figure (i). After a few days, it was observed that parts A and B of the plant acquired new positions as shown in Figure (ii).
- Name the phenomenon exhibited by the position of plant parts A and B in Figure (ii).
- Name the stimulus (other than sunlight) which causes plant part A to grow and bend upwards, and plant part B to bend downwards.
Differentiate phototropism from photonasty.
The stimulus in the process of thigmotropism is:
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 sunflower. These two plants show ______ and ______ movements.
Heliotropism is a kind of ______.
List two differences between the movement of leaves of a sensitive plant and the movement of a shoot towards light.
Name the following:
The tropic movement of plant parts in response to chemicals.
Arrange and rewrite the terms in the group in the correct order so as to be in a logical sequence, beginning with the term that is underlined.
Apical meristem, Positive phototropism, Auxins, Cell elongation.
