Tag: sense organs in animals

Questions Related to sense organs in animals

In plant tissue culture experiments, high auxin to cytokinin ratio favours .............. development and high cytokinin to auxin ratio favours .............. development.

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Root, shoot

  2. Shoot, root

  3. Root, root

  4. Shoot, shoot

Show answer
Correct Option: A
Explanation:
Callus is an unorganized, undifferentiated mass of diving cells formed during tissue culture which requires both auxins and cytokinins for its growth and differentiation. In callus, shoot regeneration is promoted by a cytokinin, such as BAP (Benzylaminopurine) and root regeneration is promoted by an auxin, such as NAA (Naphthalene acetic acid). Thus, shoot and root regenerations in callus are controlled by auxin-cytokinin balance. Usually, an excess of auxins promote root regeneration and that of cytokinins promote shoot regeneration.
So the correct option is 'root, shoot'.

Small cut pieces of soft stems are placed in growth medium with following plant hormone. Which combination of plant hormones will show the slowest growth? 

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Auxin+Cytokinin

  2. Gibberellins+Auxin

  3. Gibberellins+Cytokinin

  4. Abscisic Acid+Auxin

Show answer
Correct Option: D
Explanation:

Abscisic acid is growth inhibiting hormone whereas auxin, gibberellin and cytokinin are growth promoting hormones. Options A,B, and C include all growth promoting hormones whereas option D includes both growth promoting and growth inhibiting hormones. Therefore, this combination of hormones will show slowest growth.

So option D is the correct answer.

Cytokinin and auxin are antagonistic in which of the following function?

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Cell division

  2. Phototropism

  3. Apical dominance

  4. Geotropism

Show answer
Correct Option: C
Explanation:
  • The main function of Auxin is to promote stem elongation and inhibition of growth of lateral buds to maintain apical dominance.
  • It is produced in the stem tips, buds and root tips to promote growth and it also helps to repair wounds in plants.
  • The function of cytokinins is to increase the cell division by stimulating the process of mitosis which helps in plant growth and formation of shoots and buds.
  • Cytokinins promote sprouting of lateral buds and overcome apical dominance.
  • Cytokinin and auxin are antagonistic for apical dominance.
  • So the correct answer is 'Apical dominance'.

Rooting plant hormone is 

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. $IBA$

  2. $2, 4-D$

  3. $2,4,5-T$

  4. $NAA$

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Correct Option: A

I. ACTH
II.GH
III.MSH
IV.FSH
V.LH
VI.Oxytocin
Which of the above hormones are polypeptide or proteinaceous in nature?

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. I,II,III and IV

  2. III,IV ,V and VI

  3. III,IV ,V and VI

  4. I,II,III and VI

Show answer
Correct Option: A

Which of the following plant hormones is not acidic in nature?

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Gibberellin

  2. Auxin

  3. Cytokinin

  4. ABA

Show answer
Correct Option: A

Which of the following statement/s is/are incorrect?

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Auxin is synthesized at shoo tip

  2. Due to auxin, plant appears to bend towards dark

  3. Gibberellins help in the growth of stem

  4. cell division is promoted by cytokinin

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Correct Option: A

Identify the incorrectly matched pair.

biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. Auxin - Phototropism

  2. Gibberellins - Foolish seedling disease of rice

  3. Ethylene - Induces fruit ripening

  4. Cytokinin's - Promote apical dominance

Show answer
Correct Option: A

Match the names of the phytohormones with the roles listed. 

   List I    List II
 A  Auxin  p  Internodal elongation
 B  Gibberellin  q  Cell division
 C  Cytokinin  r  Ripening of fruits
 D  Ethylene  s  Abscission
     t  Apical dominance
biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. A- t, B- p, C- s, D- q

  2. A- t, B- p, C- q, D- s

  3. A- t, B- p, C- q, D- r

  4. A- t, B- s, C- p, D- q

Show answer
Correct Option: C
Explanation:
  • Auxin hormone causes apical dominance. Apical dominance is referred to the growth of plants attaining height. As a result of this, the plant will grow tall. Cytokinin is the phytohormone which is responsible for the multiplication if cells or cell division. 
  • In other words, cytokinin influences mitosis. Gibberellin is the hormone that induces internodal elongation. It is also called as bolting. This is commonly found in cabbage when this hormone is more in amount.
  •  The ethylene hormone is responsible for the ripening of fruits. Spraying of ethylene will promote early fruit ripening.

Match Column I with Column II and select the correct option from the codes given below.

Column I  Column II
 A. Auxin  1. Flowering
 B. Cytokinins  2. Phototropism
 C. Gibberellins  3. Stimulation of cell division
 D. Abscisic acid  4. Suppression of cell division
 E. Ethylene  5. Stomatal opening and closing
  6. Growth of lateral buds 
   7. Root growth
biology life processes: control and coordination control and coordination in plants growth in plants chemical coordination in plants animal senses sense organs in animals sense organs in humans

  1. A- 2, B- 7, C- 3, D- 5, E- 4

  2. A- 2, B- 3, C- 5, D- 7,E- 4

  3. A- 2, B- 5, C- 3, D- 4,E- 7

  4. A- 5, B- 2, C- 3, D- 7,E- 4

Show answer
Correct Option: A