Tag: plants and animal hormones

Questions Related to plants and animal hormones

Cytokinin and ethylene have oppsite effect on:-

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

  1. Leaf senescence

  2. Elogation of stem

  3. Lateral swelling of stem

  4. Winter dormancy

Show answer
Correct Option: A
Explanation:

Cytokinins are the plant hormones that are responsible for cell division and elongation, their help in the delay of leaf senescence as they transport nutrients to these parts. Ethylene is a gaseous hormone and is responsible for transverse growth as swelling of the stem, It hastens the senescence of leaves due to the evolution of ethylene gas.

So, the correct option is 'Leaf senescence'.

Find the correct application of cytokinin.

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

  1. Acts as anti-transparent and induces closure of stomata

  2. To promote root development on various types of cuttings

  3. In tea plantation for giving bushy appearance

  4. Promotes parthenocarpy in fruits like banana and grapes

Show answer
Correct Option: A

Kinetin was first isolated and identified by

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

  1. Charles Darwin

  2. Boysen and Jansen

  3. Paal

  4. Miller

Show answer
Correct Option: D
Explanation:

Kinetin is a type of cytokinin, a class of plant hormone that promotes cell division. Kinetin was originally isolated by Miller and Skoog et al., as compound from autoclaved herring sperm DNA that had cell division-promoting activity.

The chief role of CK is 

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

  1. To check abscission

  2. To check senescence

  3. To mobilize solutes

  4. To check senescence and to mobilize solutes from one part to other

Show answer
Correct Option: D
Explanation:

Cytokinin hormone does the major function of checking senescence and mobilising solutes from one part to another. It promotes the cell division or cytokinesis, in plant roots and shoots.

So, the correct answer is option D.

Phytocytomine is a

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

  1. Kinetin

  2. Giberellin

  3. Auxin

  4. None of the above

Show answer
Correct Option: A
Explanation:

Phytocytomine is a plant growth regulator. It is a kind of kinetin. It is synthesized from Licheniformis bacillus.

Which of the following contains cytokinin?

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

  1. Coconut milk

  2. Young kernels of maize

  3. Fruit of cucurbits

  4. Both (A) and (B)

Show answer
Correct Option: D
Explanation:

Coconut milk and young kernels of maize contains cytokinin. Cytokinis are a class of plant growth substances that promote cell division, or cytokinesis in plant roots and shoots. It is an adenine derivative.

Cytokinin involves

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

  1. Kinetin, zeatin, BAP

  2. $GA _3$,IBA, Kinetin

  3. Zeatin, $GA _3$, BAP

  4. IAA, Zeatin, kinetin

Show answer
Correct Option: A

Which one of the following is not true about kinetin?

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

  1. It promotes bud growth.

  2. It defers senescence.

  3. It helps in retention of chlorophyll.

  4. It inhibits the cell division.

Show answer
Correct Option: D
Explanation:

Kinetin is a type of cytokinin, a class of plant hormone that promotes cell division. Kinetin was originally isolated by Miller and Skoog et al as a compound from autoclaved herring sperm DNA that had cell division-promoting activity.

Kinetin was isolated by ...............

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

  1. Skoog and Miller

  2. Darwin and Lamarck

  3. Boysen and Jensen

  4. Went and Smit

Show answer
Correct Option: A
Explanation:

Kinetin is a type of cytokinin, a class of plant hormone that promotes cell division. Kinetin was originally isolated by Miller and Skoog et al, as a compound from autoclaved herring sperm DNA that had cell division-promoting activity. It was given the name kinetin because of its ability to induce cell division, provided that auxin was present in the medium. Kinetin is often used in plant tissue culture for inducing formation of callus and ti regenerate shoot tissues from callus.

Which of the following is not properly matched?

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

  1. Explant - excised plant part used for callus formation

  2. Cytokinins - root initiation in callus

  3. Somatic embryo - embryo produced from a vegetative cell

  4. Anther culture - haploid plants

  5. Callus - undifferentiated mass of cells

Show answer
Correct Option: B
Explanation:

Plant cells are totipotent means, each cell retains total potential to generate a new plant. Callus is an undifferentiated mass of cell generated in plant tissue culture from meristematic cells from which entire plant can be regenerated. The small piece of meristematic tissue which is used in tissue culture to generate callus is called an explant. The ratio between auxin and cytokinin is an important factor deciding initiation of roots and shoots. Phytohormone cytokinin promotes growth of shoot whereas auxin promotes growth of roots. Anther culture is done for production of haploids because anthers contain haploid microspores which can be used to generate new plants. Somatic embryos are produced by direct fusion of somatic cells one with nucleus and another without nucleus.