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प्रश्न
Give one example of a plant part which is positively hydrotropic as well as positively geotropic.
उत्तर
Roots are positively hydrotropic as well as positively geotropic.
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संबंधित प्रश्न
A potted plant is kept horizontally for a considerable time. The three positions of the parts A and B of the potted plant are shown in the following figures:
- Which figure shows the correct position taken by the parts A and B of the plant?
- What type of phenomenon is exhibited by the figure chosen in (a) above?
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 (
The climbing organs of plants like tendrils grow towards any support which they happen to touch and wind around the support. This is an example of :
(a) chemotropism
(b) nastic movement
(c) thigmotropism
(d) geotropism
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)
A potted plant is growing in a transparent glass jar. In this plant, X and Y are the two growing parts having a lot of meristematic tissue. It is observed that the part X of this plant exhibits positive geotropism but negative phototropism. On the other hand, part Y of this plant exhibits negative geotropism but positive phototropism.
(a) Name the part X of plant.
(b) Name the part Y of plant.
(c) Which part of the plant, X or Y, will exhibit positive hydrotropism?
(d) Which part of the plant, X or Y, can have tendrils on it?
(e) Which phytohormone causes the part X to exhibit negative phototropism?
The response of plants to gravity is known as geotropism. How are plant parts sensitive to gravity? Describe with the help of a diagram.
The growth of tendrils in pea plants is due to
The growth of pollen tubes towards ovules is due to
______ of sweet peas exhibit thigmotropism.
The diagram given alongside shows a type of tropism. Study the same and answer the questions that follow:
- Name and define the type of tropism shown in the diagram.
- Label the guidelines (1) to (4).
- Name two effective stimulants that help in the growth of part (2).
- Name two groups of plants where part (2) grows towards gametophyte with the help of the stimulants mentioned in (c).
