Auxin and Cytokinin Concentrations

Q.

What hormone is responsible for phototropism?

Q. Which one of the following statement regarding auxin is/are correct?

1. IAA and IBA are natural but $NAA,2,4–Dand2,4,5–T$are synthetic auxins
2. IAA and NAA are natural but IBA, 2, 4, 5–T and 2, 4–D are synthetic auxins
3. NAA and 2, 4, 5–T are natural but IAA, IBA and 2, 4–D are synthetic auxins
4. IAA, NAA, IBA, 2, 4–D and 2, 4, 5–T are synthetic auxins

Q.

Question 02:

Coconut water contains
(a) ABA
(b) auxin
(c) cytokinin
(d) gibberellin

Q. Shoot bud formation in tissue culture is promoted by

1. low auxin : high cytokinin
2. auxin : sucrose
3. $G{A}_3$ : cytokinin
4. high auxin : low cytokinin

Q. Hormone pair required for a callus to differentiate is

1. Auxin and Cytokinin
2. Cytokinin and Ethylene
3. Auxin and ABA
4. Cytokinin and Gibberellin

Q.

Does cytokinin promote root growth?

Q. Find out what the various components of the medium used for propagation of an explant in vitro are?

Q. Callus can form shoot or root by changing ratio of

1. auxin to gibberellin
2. auxin to cytokinin
   
3. cytokinin to ethylene
   
4. gibberellin to cytokinin

Q. Plant cells are totipotent. Why?

Q. Choose the wrongly matched pair from the following.

1. Auxins – “to grow”
2. Gibberellins – “Gibberella fujikuroi”
3. Cytokinins – Herring sperm DNA
4. Abscisic acid – Flowering hormone

Q. In tissue culture, callus can be induced to form shoot or root by altering the ratio of:

1. Auxin to cytokinin
2. Cytokinin to ethylene
3. Auxin to gibberellin
4. Gibberellin to cytokinin

Q. Auxin can be bioassayed by:

1. Lettuce hypocotyl elongation
2. Avena coleoptile curvature
3. Hydroponics
4. Potometer

Q.

Fill in the blanks.

A. Maximum growth is observed in ...............phase.

B. Apical dominance is due to ................

C. .............. initiate rooting.

D. Pigment involved in photoreception in flowering plants in .........

Q. The total time in which growth occurs is called as

1. Phase of maturation
2. Phase of cell division
3. Grand period of growth
4. Phase of elongation

Q. In plant tissue culture, plant tissues can be regenerated into complete plantlets primarily by altering the concentrations of

1. Vitamins
2. Sugars
3. Amino acids
4. Hormones

Q. Why is pollen pistil interaction a dynamic process?

Q. You are given a tissue with its potential for differentiation in an artificial culture. Which of the following pairs of hormones would you add to the medium to secure shoots as well as roots?

1. Gibberellin and abscisic acid
2. IAA and gibberellin
3. Auxin and cytokinin
4. Auxin and abscisic acid

Q. When the part of shoot dies after flowering and fruiting is called as

1. Whole senescence
2. Progressive senescence
3. Top senescence
4. None of the above

Q. Hormone found in liquid endosperm of Coconut/Coconut milk factor is

1. Gibberellin
2. Auxin
3. Ethylene
4. Cytokinin

Q. Abscission is restricted to

1. Morphologically distinct region
2. Both A and B
3. Anatomically distinct region
4. Abscission is not restricted to any region

Q. who plucks the pearls from the crown of ishtar ? why does she do so ??

Q. Which of the following factor influences the abscission?

1. Light
2. Temperature
3. Air pollutants
4. All of the above

Q. Define the term 'stress' for plants. Discuss briefly the two types of stress encountered by plants.

Q. Very short answer type.
Milky endosperm of coconut is rich in which hormone?

Q.

For producing a callus from plant cells, which of the following are required?

1. gibberellin to cytokinin
2. auxin to gibberellin
3. auxin to cytokinin
   
4. cytokinin to ethylene