Tag: cytokinins

Questions Related to cytokinins

Multiple choice biology chemical coordination in plants cytokinins plant hormones plants and animal hormones

Natural cytokinins are synthesized in tissues for

  1. Differentiating

  2. Senescent

  3. Dividing

  4. Storing food

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Cytokinin is a naturally occurring plant growth hormone (PGR) extracted from coconut milk.
Cytokinins are synthesized in root apex, endosperm of seeds, and young fruits where cell division takes place continuously. 
They stimulate cell division, cell enlargement and cell differentiation and also prevent ageing of plant parts.
Hence, natural cytokinins are synthesized in tissues for dividing.
So, the answer is C.
Multiple choice biology chemical coordination in plants cytokinins plant hormones plants and animal hormones

Hormone that is associated with retaining the chloroplast chlorophyll is ?

  1. Auxin

  2. ABA

  3. Cytokinin

  4. Gibberelins

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Cytokinin is a plant hormone which acts as plant growth regulator. It is associated with retaining the chloroplast chlorophyll in the leaves. The cytokinin has anti-senescence effect on the plant. It delays the senescence of the leaves and prevents the destruction of chloroplast.

Thus, the correct answer is option C.

Multiple choice biology chemical coordination in plants cytokinins plant hormones plants and animal hormones

Which plant hormone promotes cell division?

  1. Gibberellins

  2. Cytokinin

  3. Ethylene

  4. Auxins

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • Cytokinins(CK) are a class of plant growth hormones that promote cell division, or cytokinesis in plants roots and shoots. For example, Kinetin and benzyl-aminopurine.
  • They are involved primarily in cell growth and differentiation, but also affect apical dominance, axillary bud growth, and leaf senescence.
  • Hence the plant hormone promotes cell division is Cytokinin.
  • So, the correct answer is 'Cytokinin'.
Multiple choice biology chemical coordination in plants cytokinins plant hormones plants and animal hormones

Cytokinins helps to produce all except.

  1. New leaves

  2. Chloroplast in leaves

  3. Lateral short growth and adventitious shoot foration

  4. Rooting on cut stem

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Phytohormone concerned in the cell division is called cytokinins. It is involved in the formation of chloroplast in leaves, new leaves formation, lateral shoot growth and adventitious shoot formation.

So, the correct option is ‘rooting on cut stem’.

Multiple choice biology chemical coordination in plants cytokinins plant hormones plants and animal hormones

Choose the correct answer from the alternatives given.
Application of which of the following hormones prevents plant tissues from senescing or ageing?

  1. Abscisic acid

  2. Auxin

  3. Cytokinin

  4. Ethylene

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Cytokinins help overcome apical dominance. They promote nutrient mobilization which helps in the delay of leaf senescence.

So, the correct option is 'Cytokinin'.

Multiple choice biology chemical coordination in plants cytokinins plant hormones plants and animal hormones

Choose the correct answer from the alternatives given.
A hormone that causes cell division and is found in coconut milk or in dividing root tissue is:

  1. abscisic acid

  2. auxin

  3. cytokinin

  4. gibberelthi

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In the presence of auxin (but not in its absence) kinetin stimulated tobacco pith parenchyma tissue to proliferate in culture. Later, zeatin was identified as the first naturally occurring cytokinin in immature maize endosperm (Letham, 1973), and turns out to be the abundant cytokinin in coconut milk.

So, the correct option is 'cytokinin'.

Multiple choice biology chemical coordination in plants cytokinins plant hormones plants and animal hormones

Choose the correct answer from the alternatives given.
Cytokinins

  1. are plant hormones that promote cell division

  2. are used in combination with auxin to produce plants from undifferentiated callose tissue.

  3. also work with oligosaccharins to effect tissue differentiation

  4. all of the above.

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

It helps to produce new leaves, chloroplasts in leaves, lateral shoot growth and adventitious shoot formation. Cytokinins help overcome apical dominance. They promote nutrient mobilisation which helps in the delay of leaf senescence.

Natural cytokinins are synthesised in regions where rapid cell division occurs, for example, root apices, developing shoot buds, young fruits etc.
So, the correct option is 'all of the above'.

Multiple choice biology chemical coordination in plants cytokinins plant hormones plants and animal hormones

Cytokinins are mostly ____________.

  1. glucosides

  2. phenolics

  3. amino purines

  4. organic acids.

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Cytokinins are plant growth hormones which are basic in nature, either amino purine or phenyl urea derivatives, that promote cytokinesis (= cell division) either alone or in conjunction with auxin. Kinetin, a synthetic cytokinin, is 6-furfuryl amino purine. Zeatin, a natural cytokinin, is 6-hydroxy 3-methyl trans 2-butenyl amino purine.

Multiple choice biology chemical coordination in plants cytokinins plant hormones plants and animal hormones

Select the pair that consists of plant growth promoters only.

  1. Auxins and cytokinins

  2. Gibberellins and ABA

  3. Ethylene and ABA

  4. All of these

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Auxins and cytokinins are plant growth promoters, the roles played by auxin and cytokinin are as follows.

Auxins: Cell enlargement and longitudinal growth of root and shoot.
             Reactivation of cambium in the growth season, that is, responsible for secondary growth, promotes apical dominance and parthenocarpy, inhibits abcission.
Cytokinins: induces morphogenesis that is differentiation of cells into tissues and organs.delays senescence, breaks dormancy and promotes seed germination, enhances expression of a sexual characteristic- femaleness in some plants.
Auxin/cytokinin ratio influences root and shoot formation and growth
So, the correct answer is 'Auxins and cytokinins'