Frank solutions for Biology Part 2 [English] Class 10 ICSE chapter 7 - Chemical Coordination in Plants [Latest edition]

Avena coleoptile test to find out the quantity of growth promoting hormones was discovered by ______.

Indole-3 acetic acid, called as auxin was first isolated from ______.

Which of the following effects of auxins is of wide application?

Growth hormone acts ______.

Gibberellin was first extracted from ______.

Bolting hormone is ______.

Gibberellins are ______.

Gibberellin was first isolated from culture of ______.

Genetically dwarf plants can be made long by the application of ______.

Which of the following growth hormones can be used for the eradication of weeds?

The curvature of coleoptile towards the source of light is due to ______.

Sprouting of potato during storage can be prevented by ______.

Apparatus used to nullify the effect of geotropism is known as ______.

The most common cytokinin is ______.

The growth regulator that retards ageing of plant organ is ______.

Hormone responsible for senescence is ______.

Movement of pollen tube is an instance of ______.

Coiling of garden pea tendrils around any support is an example of ______.

‘Foolish seedling disease’ of rice led to the discovery of ______.

Phototropic curvature is the result of uneven distribution of ______.

Which is a stress hormone?

Among the following which helps in early ripening of fruits?

Movement of roots in search of moisture is called ______.

Assertion (A): The effect of auxin hormone on the growth of roots exactly opposite to that on a stem.

Reason (R): Auxin hormone increases the rate of growth in root and decreases the rate of growth in stem.

Assertion (A): Auxins promote the elongation of cells.

Reason (R): Auxins stimulate cell division in the short apical meristem.

Assertion (A): Phototropism is caused by auxin.

Reason (R): When light is coming frem one side of the plant, auxin diffuses towards the shady side of the shoot.

Name the plant hormone associated/concerned with the following:

Elongation of cell

Name the plant hormone associated/concerned with the following:

Shedding of leaves

Name the plant hormone associated/concerned with the following:

Breaking seed dormancy

Name the plant hormone associated/concerned with the following:

The only gaseous plant regulator

Name the plant hormone associated/concerned with the following:

A growth inhibitor in plants

Name the following:

A gaseous plant hormone which promotes the ripening of fruits.

Name the following:

The tropic movement of plant parts in response to chemicals.

Write short notes on:

Cytokinins

Write a short note on:

Phototropism

Write a short note on:

Geotropism

Write a short note on:

Ethylene

Name the type of movement induced in plants by light.

Name the type of movement induced in plants by gravity.

Name the type of movement induced in plants by moisture.

Which one of the plant growth regulators would you use if you are asked to:

Induce rooting in a twig

Which one of the plant growth regulators would you use if you are asked to:

Quickly ripen a fruit

Which one of the plant growth regulators would you use if you are asked to:

Delay leaf senescence

Which one of the plant growth regulators would you use if you are asked to:

Induce growth in axillary buds

Mention any two physiological effects of auxins.

Distinguish between phototropism and geotropism.

Name the part of plant which shows positive geotropism. Why?

Write full form of  2,4-D

Mention one use of 2,4-D.

Name five main classes of plant hormones.

Define plant movement.

How is movement in plants different from that in animals?

Abscisic acid is a growth inhibiting hormone. How is it useful to plants?

Write the main functions of gibberellins.

What is a growth regulator?

Give a brief account of auxins.

What are the major differences among auxins and gibberellins?

What do you know about the role of ġibberellin in plant growth?

Write a short note on foolish seedling disease.

Write a short note on senescence.

Write a short note on abscission of leaf.

Write a short note on phytohormones.

How were gibberellins discovered?

Write the main applications of gibberellins in plants.

Write short notes on:

Thigmotropism

Write short notes on:

Chemotropism

Write short notes on:

Hydrotropism

Give biological explanations for Plants growing in fertilized soil are often found to wilt if the soil is not adequately watered.

What is Parthenocarpy?

Give one example of Parthenocarpy.

The diagram given below represents a plant movement. Answer the following questions.

1. Name the tropic movement shown in the diagram.
2. Explain the tropic movement mentioned in (a).
3. Label the part marked ‘A’.
4. What is part A attracted to?
5. Give an example of a plant which shows thigmotropism.

Given below is an experimental setup to demonstrate a particular tropic movement in germinating seeds. Study the diagram and answer the questions that follow:

1. Label the parts 1 and 2.
2. Name the tropic movement shown by part 1.
3. Part 1 is affected by two stimuli. Name them. Which one of the two is stronger?
4. What is thigmotropism? Give one example.
5. What is meant by 'Positive' and 'Negative' tropic movements in plants?

Study the diagram given below and answer the questions that follow:

1. Name the phenomenon depicted by the shoot in the above diagram.
2. Which plant hormone plays an important role in the above movement?
3. Complete and rewrite the given statement by filling in the correct terms:
   Shoots show positive ______ whereas, roots show positive ______.

Ali has some pea plants in his garden which need a support to grow as seen in the picture given below:

1. Name the phenomenon depicted by the shoot in the given figure.
2. Define the above phenomenon.
3. Write the name of the part marked X.