Growth Related Movement in Plant

Q.

The day-neutral plant is

1. Tomato

2. Tobacco

3. Wheat

4. Oat

Q.

Describe one way how plants respond to stimuli.

Q.

What are tropic movements in plants?

Q.

(a) What is meant by 'tropisms' (or tropic movements )? Explain with an example.

(b) What are the different types of tropisms? Define each type of tropism. Write the name of the stimulus in each case.

(c) How does tropism differ from nasties (or nastic movements)?

Q. Amongst the following which one is growth inhibiting hormone?

1. Cytokinin
2. Auxin
3. Abscisic acid
4. Gibberellin

Q.

Distinguish between tropic movements and nastic movements in plants. Give examples to illustrate your answer.

Q.

Auxins are produced by

1. Old leaves

2. Fruits

3. Buds

4. Wood

Q.

(b) What is the difference between photonasty and thigmonasty?

Q. In the absence of muscle cell how do plant cell show movement

Q.

What are tropic movements ? Briefly explain various types of tropic movements in plants.

Q.

What is meant by positive and n egative tropic movements in plants ? Explain them by giving suitable examples.

Q.

How do auxins promote the growth of a tendril around a support?

Q.

What is positive phototropism?

Q. Statement 1: The movement of sunflower in response to day or night is quite slow.
Statement 2: Growth related movements of plants are even slower.

1. Only 2 is correct
2. Only 1 is correct
3. Both 1 & 2 is are correct
4. Both are wrong

Q.

To which directional stimuli do :

(a) roots respond?

(b) shoots respond?

Q.

Give the scientific terms used to represent the following:

(a) Bending of a shoot towards the light.

(b) Growing roots towards the earth.

(c) The growth of a pollen tube towards ovule.

(d) Bending roots towards the water.

(e) The winding of tendril around a support.

Q.

(a) What is meant by positive tropism and negative tropism? Explain with examples.

(b) Define thigmotropism. Give one example of thigmotropism.

(c) What is the difference between thigmotropism and thigmonasty? Name one plant which exhibits thigmotropism and one plant which exhibits thigmonasty. What behaviour (or responses) of these plants make you think that they exhibit thigmotropism and thigmonasty respectively?

Q.

While conducting experiments to study the effect of various stimuli on the plants, it was observed that the roots of a plant X grow and bend towards two stimuli A and B but bend away from a third stimulus C. The stem of the plant X, however, bends away from stimuli A and B but bends towards the stimulus C. The stimulus B is known to act on the roots due to too much weight of the earth. Keeping these points in mind, answer the following questions :

(a) What could stimulus A be?

(b) Name the stimulus B.

(c) What could stimulus C be?

(d) The branches of a fallen tree in a forest grow straight up in response to two stimuli. What could be these two stimuli out of A, B and C? Also, name these two stimuli.

Q.

The growth of tendrils in pea plants is due to the :

(a) effect of sunlight on the tendril cells facing the sun

(b) effect of gravity on the part of tendril hanging down towards the earth

(c) rapid cell division and elongation in tendril cells that are away from the support

(d) rapid cell division and elongation in tendril cells in contact with the support

Q.

Why is abscisic acid called the stress hormone?

Q.

Fill in the following blanks:

(a) A plant's response to light is called .................

(b) A plant's response to gravity is called .................

(c) Plant shoot grow upward in response to ..............

(d) Plant roots grow downward in response to .............

(e) Tendrils wind around a support in response to ..........

(f) Plant roots grow towards .......... and in the direction of force of ...............

(g) A root of a plant grows downward. This is known as ..............

(h) ........... is the hormone that causes phototropism in plants

(i) The response of leaves to the sunlight is called ..............

Q. ________ is a growth-independent movement in plants.

1. Phototropism
2. Thigmonasty
3. Hydrotropism
4. Geotropism

Q.

Name the plant part:

(a) which bends in the direction of gravity but away from light

(b) which bends towards light but away from the force of gravity

Q. What causes a tendril to encircle or coil around the object it comes in contact with? Explain the process involved.​

Q.

Why does abscisic acid inhibit growth?

Q.

Abscisic acid brings ripening of fruits.

1. True
2. False

Q.

Name hormones associated with growth-inhibiting activities like seed dormancy and shedding of leaves.

Q. The movement or growth of any part of a plant in response to an external stimulus is called tropism or tropic movement.

1. True
2. False

Q.

Response of a plant towards surface or contact is called:

1. Phototropism

2. Geotropism

3. Thigmotropism

4. Tropism

Q.

What is the movement of plant due to touch is called?