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प्रश्न
What are the different types of tropisms? Define each type of tropism. Write the name of stimulus in each case
उत्तर
The different types of tropisms are:
(i) Phototropism: The movement of plant parts in response to light is known as phototropism. The stimulus is light.
(ii) Geotropism: The movement of plant parts in response to gravity is known as geotropism. The stimulus is gravity.
(iii) Hydrotropism: The movement of plant parts in response to water is known as hydrotropism. The stimulus is water.
(iv) Chemotropism: The movement of plant parts in response to chemicals is known as chemotropism. The stimulus is chemicals.
(v) Thigmotropism: The movement of plant parts in response to touch is known as thigmotropism. The stimulus is touch.
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संबंधित प्रश्न
Design an experiment to demonstrate hydrotropism.
What is the stimulus in chemotropism?
The stimulus in the process of thigmotropism is ______.
The top part A of the flask-shaped reproductive organ X in the flower of a plant secrets a surgery substance into its lower part B which goes towards the bottom part C of the flask-shaped organ. When a tiny grain D coming from the top part E of another reproductive organ Y i the flower falls on part A, it grows a long tube F through the organ X i response to the sugary substance and reaches the bottom part C of flask-shaped organ to carry out fertilisation.
(a) Name parts (i) organ X, and (ii) organ Y, inside the flower?
(b) Name parts (i) A (ii) B, and (iii) C, of flask-shaped organ.
(c) Name (i) grain D, and (ii) part E of organ Y.
(d) Name the tube F.
(e) What is the phenomenon of growing a long tube in response to sugary substance in the process of fertilisation in a flower known as?
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.
Roots of plants are:
The opening and closing of the Moonflower is not a tropism because the movement in this is ______.
Name a plant hormone responsible for bending of a shoot of a plant when it is exposed to unidirectional light. How does is promote phototropism?
Name the stimulus which causes the following movement in plant:
Geotropism
Given below are the figures showing some kinds of tropic movements in plants. Study the same and answer the following questions:
- Which one of these figures is correct? Give reason in support of your answer.
- Name the kinds of movements shown by the root system and shoot system. Define each.
- What are the two stimuli which affect root system and shoot system positively? Name them.
- Which of the following stimuli affects the growth of the root strongly?
- Gravity
- Water
- Draw a neat and labelled diagram of the longitudinal section of a pistil showing chemotropism in an angiospermic plant.
