Ethylene

Q. Which one of the following hormones play an important role in seed development, maturation and dormancy?

1. ABA
2. IAA
3. GA
4. CK

Q. Who among the following discovered ethylene?

1. Skoog and Miller
2. E. Kurosawa
3. H.H. Cousins
4. C. Darwin and F. Darwin

Q.

What plant hormone causes seeds to germinate?

Q. Which of the following statement(s) concerning ethephon is/are true?
I. It is commercially used to ripen fruits
II. It is the source of ethylene
III. Plants can easily absorb and transport ethephon in solution

1. II and III
2. Only I
3. I and II
4. I, II, and III

Q. Refer the following statements.
(i) Promotes flowering in pineapple.
(ii) Used to prepare weed free lawn.
(iii) Promotes the abscission of older mature leaves and fruits.
The above functions are carried out by

1. GA
2. ABA
3. Auxin
4. Ethylene

Q.

How do Auxin and Cytokinin work together?

Q. Calling the biosynthetic phase as the dark reaction is a misnomer? Discuss.

Q.

What does gibberellic acid enable plants to do?

Q. Which of the following is a synthetic auxin?

1. IAA
2. IBA
3. ABA
4. NAA

Q.

Which one of the following is incorrect with reference to ethylene?

1. Promotes rapid internode/petiole elongation in rice

2. Causes synchronous senescence of leaves in tobacco

3. Promote root growth and root hair formation and increases transpiring surface.

4. Breaks seed and bud dormancy

Q. Ripe fruits soften due to

1. Exosmosis.
2. Degeneration of cell walls
3. Metabolism of tannins
4. Partial solubilisation of pectic compounds

Q.

Which of the following is a natural plant growth regulator?

1. NAA

2. Ethylene

3. NBA

4. 2; 4-D

Q. Abscisic acid is also known as

1. $\text{inhibitor}\beta$
2. $\text{dormin}$
3. $\text{abscisin II}$
4. $\text{all the above}$

Q. Rooting in stem cuttings is commonly stimulated by using

1. benzylaminopurine
2. abscisic acid
3. ethylene
4. indole butyric acid

Q. Pineapple can be made to flower in off season by the application of

1. ethylene
2. short-days
3. low temperature
4. zeatin

Q. Induction of cell division and delay in senescence is done by

1. cytokinin
2. kinetin
3. gibberellin
4. auxin

Q. Stem elongation is known to be influenced by

1. auxins and kinins
2. florigen and gibberellins
3. gibberellins and auxins
4. auxins and florigen
   
   

Q. Cytokinins and ethylene have opposite effects on:

1. Leaf senescence
2. Elongation of stem
3. Lateral swelling of stem
4. Winter dormancy

Q. Which one is paired incorrectly?

1. Gibberellin - Discovered from fungus Giberella fujikuroi
2. Abscisic acid - Volatile substance from ripened oranges
3. Auxin - Isolated from tips of coleoptiles
4. Kinetin - Cytokinesis promoting active substance

Q.

Common gibberellin is.

1. GA₁

2. GA₂

3. GA₃

4. GA₁₇

Q.

What are the five main plant hormones?

Q. Which hormone plays an important role in the formation of roots?

1. NAA
2. 2, 4-D
3. IAA
4. ABA

Q. Chemical name of ethephon is __.

Q. Highest concentration of auxin exists

1. at the base of various plant organs
2. in growing tips of plants
3. in leaves
4. in xylem and phloem cells only

Q. Ethylene is a simple gaseous phytohormone that is synthesised from .

1. tryptophan
2. methionine
3. tyrosine
4. acetyl CoA

Q. While conducting an experiment on plant hormones a student found that on using a particular hormone abscission of leaves, senescence, cell division and growth was observed. Which hormone do you think was used on the plants?

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

Q. If a planter is interested in obtaining a good crop of tea leaves from a single plant, he should

1. feed auxin to the plant through soil
2. remove the apical bud of the main shoot and the branches
3. cut off the tip of the plant and then apply auxin to the cut end
4. supply auxin from the tip of the plant as well as through roots

Q.

Through which process is water absorbed by root hair?

Q. How many following statements are correct for ethylene ?

1. 1
2. 2
3. 3
4. 4

Q.

What are the chemical substance that perform control and coordination in plants called?