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

A plant hormone used for inducing morphogenesis in plant tissue culture

is ........................

  1. Abscisic acid

  2. Gibberellins

  3. Cytokinins

  4. Ethylene
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Morphogenesis is the process of organ formation. Cytokinin is a plant hormone which plays a major role in organ formation or morphogenesis with the presence of auxin. It helps in rapid multiplication of cells by repeated cytokinesis and karyokinesis.

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

Cytokinesis refers to ................

  1. Division of chromosomes

  2. Division of cytoplasm

  3. Division of nucleus

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cytokinin is a plant hormone which is vital for the mitotic divisions taking place in plants. It thus enables cytokinesis and karyokinesis in the cells. This makes cytokinin an important constituent in callus culture.

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

Cytokinins are mostly produced in

  1. Shoot apex

  2. Root apex

  3. Young leaves

  4. Lateral buds
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cytokinin is a plant hormone. It promotes cell division. It also delays the destruction of chlorophyll and protein. It shows delay of senescence in leaves.  It is mostly produced in the root apex. When an excised leaf is induced to root, it does not turn yellow because root apex synthesizes cytokinin hormone.

Thus, the correct answer is option B.

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

Delay in senescence is caused by the spray of 

  1. IBA

  2. GA

  3. Cytokinin

  4. ABA
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Senescence means aging. Cytokinin is a plant hormone. It plays major role in cell proliferation and cell division. During senescence, cytokinin levels are low. It delays in senescence of leaves when sprayed externally by delaying the destruction of chlorophyll and proteins in leaves. 

Thus, the correct answer is option C.

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

Cytokinins are generally

  1. Acids

  2. Aminopurines

  3. Phenols

  4. Glucosides
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The first cytokinin discovered was an aminopurine derivative named kinetin. Except zeatin which is adenine derivative, all other present cytokinins are aminopurines. All the naturally occurring cytokinins are substituted purines, in which sixth carbon is substituted by amino group.

Thus, the correct answer is option B.

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

Kinetin like properties are present in

  1. Pineapple

  2. Soyabean

  3. Groundnut

  4. Coconut milk
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Kinetin is a type of cytokinin which is a plant hormone. It promotes cell division. The first known cytokinin hormone was found in coconut milk. Coconut milk is liquid endosperm. It promotes cell division same as kinetin. It stimulates the embryo to grow when it is supplied with food.

Thus, the correct answer is option D.

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

Flowering in some short day plants is promoted by

  1. Auxins

  2. Gibberellins

  3. Cytokinins/ABA

  4. Ethylene
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Gibberellin is a plant hormone which helps in growth of stem. The rapid growth and flowering with cell division and cell elongation is called as bolting. Bolting requires either long days or cold treatment. Bolting can be induced by higher level of gibberellin under normal conditions. Hence, it induces flowering in some short day plants.

Thus, the correct answer is option B.

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

Cytokinins have the ability to

  1. Induce morphogenesis

  2. Substitute cold treatment

  3. Convert dwarf plants to tall plants

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cytokinins are plant hormones that are involved in various physiological processes. They promotes cell division by stimulating mitosis. Due to increased rate of mitosis, they induce shoot and root morphogenesis. They also plays important role in formation of fruits and seeds.

Thus, the correct answer is option A.

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

Cut pr excised leaves remain green for long if induced to root or dipped in

  1. Gibberellins

  2. Cytokinins

  3. Auxins

  4. Ethylene
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cytokinin is a plant hormone. It promotes cell division. It also delays the destruction of chlorophyll and protein. It shows delay of senescence in leaves and keeps leaves green for long time. So when cut or excised leaves are induced to root, it will remain green because root synthesizes cytokinin hormone.

Thus, the correct answer is option B.