Tag: plant growth

Questions Related to plant growth

Multiple choice biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

Find out correct options.

   I      II      III
a Foolish plant p Volatile hormone x Induces dormancy
b Induces senescence q Abscisic acid y Ripens fruit
r Gibberella z Usually sterile plant
  1. a- p- y, b- r- x

  2. a- r- z, b- q- z

  3. a- r- z, b- p- y

  4. a- q- x, b- r- y

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

The foolish seedling disease affects the rice plant through the roots or crowns. It is caused by the fungus Gibberella fujikuroi. It is the source of gibberellin hormone. The plant is usually sterile. Abscisic acid is a plant hormone that induces senescence in plants. Under stress environmental condition, it induces seed dormancy.

Thus, the correct answer is option B.

Multiple choice biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

The primary and secondary growth of a shoot is inhibited by

  1. Auxin

  2. Gibberellin

  3. Cytokinin

  4. Abscisic acid

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

Abscisic acid is a plant hormone. It is growth inhibitor hormone. Its primary role is inhibition of growth of root, shoot, leaf, etc. It inhibits primary and secondary growth of shoot. During stress condition, its concentration increases.

Thus, the correct answer is option D.

Multiple choice biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

State whether the following statements are true or false.
A cut woody stem exposed to a cytokinin solution will be induced to grow roots rapidly.

  1. True

  2. False

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

cytokinins are the plant growth regulators that promote cell division, they function similar to auxin and helps in cell elongation and are majorly present in the roots and then passes through the xylem. They perform many functions like cell division, embryo and endosperm formation, and growth of root cells etc.

So, the correct statement is 'True'.

Multiple choice biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

Kinetin, a modified form of adenine was discovered from

  1. Autoclaved herring sperm DNA

  2. Coconut milk

  3. Corn kernel

  4. Fungus

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

Kinetin is a modified form of adenine which is discovered by Miller and Skoog as a compound from autoclaved herring sperm DNA. Herring is a fish. From it's sperm, DNA is isolated which is sterilized using steam at high pressure which is called autoclaved herring sperm DNA. From this, kinetin was isolated which has ability to induce cell division.

Thus, the correct answer is 'Autoclaved herring sperm DNA.'

Multiple choice biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

Horizontal growth of seedlings, swelling of axis and apical hook formation in dicot seedlings is brought about by

  1. Auxins

  2. Gibberellins

  3. Ethylene

  4. Kinetin

  5. Abscisic acid

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Ethylene is a gaseous plant hormone. It is also called as ripening hormone as it stimulates ripening of fruits. It also promotes the horizontal growth of seedlings, swelling of the axis and increase curvature by apical hook formation in dicot seedlings. It inhibits stem elongation. This is called as triple response shown by ethylene.
Thus, the correct answer is option C.
Multiple choice biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

Which is not the effect of ethylene?

  1. Promotes senescence and abscission of plant organs

  2. Breaks seed and bud dormancy

  3. Brings about horizontal growth of seedlings

  4. Hastens fruit ripening

  5. Helps to overcome apical dominance

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

Ethylene is a plant hormone. It is also called as ripening hormone as it hastens fruit ripening in plants. In certain plants, it breaks seed and bud dormancy and induces germination. It also causes flowers to fall from the plant and hence, promotes senescence and abscission of plant hormones. It also causes the triple response in etiolated seedlings. It inhibits stem elongation and brings about the horizontal growth of seedlings. 

Thus, the correct answer is option E.

Multiple choice biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

Ethylene promotes water absorption by increasing the root's absorption surface. It promotes:

  1. Premability of cell membrane

  2. Rormation of root hairs

  3. Concentration of cell sap

  4. All of these

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Ethylene promotes water absorption by increasing the root's absorption surface. It promotes the elongation of the root hairs and the root itself and it is also responsible for increasing the cell permeability in some cases. It has also been observed to increase the osmotic pressure and the concentration of cell sap.

So, the correct answer is 'all of these'.
Multiple choice biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

Artificial ripening of fruit is carried out by

  1. Auxin

  2. Gibberellin

  3. Abscisic acid

  4. Ethylene

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

Ethylene is sprayed on fruits to promote artificial ripening, which is very commonly seen in fruit shops.
Ethylene is applied on fruits in the form of a spray. It acts to the fruit cell wall made of pectin or cellulose and promotes ripening.

Multiple choice biology plant growth control of blood glucose hormones in human reproduction testes and ovary

Match the Column-I & Column-II.

(i) Auxin (A) Ripening of fruit
(ii) ABA (B) Bolting
(iii) Gibberellin (C) Sensitivity against adverse conditions
(iv) Ethephon (D) parthenocarpy in tomato
  1. i-C, ii-D, iii-B, iv-A

  2. i-D, ii-C, iii-A, iv-B

  3. i-D, ii-C, iii-B, iv-A

  4. i-A, ii-C, iii-B, iv-D

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

  • (i) Auxin - (D) parthenocarpy in tomato -Auxins are generally produced by the growing apices of the stems and roots, from where they migrate to the regions of their action. Auxins also induce parthenocarpy in
tomatoes. 
  • (ii) ABA - (C) Sensitivity against adverse conditions -ABA(Abscisic acid) acts as a general plant growth inhibitor and an inhibitor of plant metabolism.ABA regulates sensitivity against adverse conditions i.e ABA stimulates the closure of stomata in the epidermis and increases the tolerance of plants to various kind of stresses. Therefore, it is also called the stress hormone.
  • (iii) Gibberellin - (B) Bolting -Gibberellins promotes bolting
(internode elongation just prior to flowering) in beet, cabbages and many
plants with rosette habit.
  • (iv) Ethephon - (A) Ripening of fruit - Ethephon in an aqueous solution is readily absorbed and transported within the plant and releases ethylene slowly. Ethephon hastens fruit ripening in tomatoes and apples.
  • So, the correct answer is 'i-D, ii-C, iii-B, iv-A'.