Tag: biology

Questions Related to biology

Transport of cytokinin in the plant body is

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

  1. Basipetal

  2. Lateral

  3. Acropetal

  4. On all sides

Show answer
Correct Option: C
Explanation:

Cytokinin is a plant hormone that is synthesized in the root. It shows acropetal transport. It is exactly opposite to the basipetal transport of auxin hormone. Acropetal transport is the translocation of hormone towards the shoot apex.

Thus, the correct answer is option C.

Natural cytokinins are synthesised in tissues that are

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

  1. Storing food

  2. Differentiating

  3. Dividing

  4. Senescent

Show answer
Correct Option: C
Explanation:

Cytokinin is a plant hormone that is involved in various physiological processes. It is growth promoting hormone. It stimulates cell division or cytokinesis and hence the name was given. It is synthesized in high concentration in tissues that are dividing such as cambium.

Thus, the correct answer is option C.

Natural cytokinins are synthesized in tissues for

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

  1. Differentiating

  2. Senescent

  3. Dividing

  4. Storing food

Show answer
Correct Option: C
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.

The precursor of Serine and Cytokine is?

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

  1. Oxalocetate

  2. $3$-phosphoglycerate

  3. Phosphoenolpyruvate

  4. Erythrose-$4$-phosphate

Show answer
Correct Option: A

Hormone that is associated with retaining the chloroplast chlorophyll is ?

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

  1. Auxin

  2. ABA

  3. Cytokinin

  4. Gibberelins

Show answer
Correct Option: C
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.

Which plant hormone promotes cell division?

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

  1. Gibberellins

  2. Cytokinin

  3. Ethylene

  4. Auxins

Show answer
Correct Option: B
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'.

Cytokinins helps to produce all except.

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

  1. New leaves

  2. Chloroplast in leaves

  3. Lateral short growth and adventitious shoot foration

  4. Rooting on cut stem

Show answer
Correct Option: D
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’.

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

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

  1. Abscisic acid

  2. Auxin

  3. Cytokinin

  4. Ethylene

Show answer
Correct Option: C
Explanation:

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

So, the correct option is 'Cytokinin'.

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:

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

  1. abscisic acid

  2. auxin

  3. cytokinin

  4. gibberelthi

Show answer
Correct Option: C
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'.

Choose the correct answer from the alternatives given.
Cytokinins

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

  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.

Show answer
Correct Option: D
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'.