Tag: biology

Questions Related to biology

Choose the correct answer from the alternatives given.
Which of the following plant hormone is a gas?

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

  1. Auxin

  2. Cytokinin

  3. Ethylene

  4. Gibberellin

Show answer
Correct Option: C
Explanation:

Ethylene is a small hydrocarbon gas. Ethylene is responsible for the changes in texture, softening, colour, and other processes involved in ripening. 

So, the correct option is 'Ethylene'.

Artificial ripening of fruits is caused by the treatment of

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

  1. IAA

  2. NAA

  3. Ethylene

  4. Kinetin.

Show answer
Correct Option: C
Explanation:

Artificial ripening of fruits is caused by the treatment of ethylene. This process is achieved by spraying a commercial product Ethephon, that releases ethylene gradually on aerobic degradation. It is generally used for the faster ripening of cotton, wheat, coffee, tobacco, rice etc

So, the correct answer is 'Ethylene'

Gibberellins promote the formation of  A  flowers on genetically  B  plants in Cannabis whereas ethylene promotes formation of  C  flowers on genetically  D  Cannabis plants.

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

  1. A-male, B-female, C-female, D-male

  2. A-male, B-male, C-female, D-female

  3. A-female, B-male, C-male, D-female

  4. A-female, B-female, C-male, D-male

Show answer
Correct Option: A
Explanation:
Gibberellins are growth hormones that stimulate cell elongation and cause plants to grow taller. Gibberellins also have a role in other plant processes, such as stem elongation, germination, flowering, and fruit ripening. Gibberellins promote the formation of male flowers on genetically female plants in Cannabis whereas ethylene promotes formation of female flowers on genetically male Cannabis plants.
 So, the correct answers are "A- Male, B- Female, C- Female, D- Male."

Ethylene is used for _________________.

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

  1. retarding ripening of tomatoes

  2. hastening of ripening of fruits

  3. slowing down ripening of apples

  4. both (b) and (c).

Show answer
Correct Option: B
Explanation:

Ethylene is a fruit ripening hormone. It stimulates the biochemical changes which take place upon fruit ripening.

The most widely used compound as a source of $C 2H _4$ is ___________.

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

  1. kinetin

  2. zeatin

  3. IBA

  4. ethephon

Show answer
Correct Option: D
Explanation:

Ethephon, 2-chloroethyl phosphonic acid (Ethrel) is a source of ethylene used commercially. It is used in aqueous solution and releases ethylene slowly.

A farmer grows cucumber plants in his field. He wants to increase the number of female flowers in them. Which plant growth regulator can be applied to achieve this?

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

  1. ABA

  2. Ethylene

  3. GA

  4. Cytokinins

Show answer
Correct Option: B
Explanation:

Ethylene has a feminising effect on sex expression. The genetically male plants of cucumber can be induced to produce female flower in the presence of ethylene. The number of female flowers and hence fruit is enhanced in these plants.

If a rotten fruit gets mixed with unripe fruits, the unripe fruits will _____________.

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

  1. also be rotten

  2. ripe quickly

  3. remain unchanged

  4. none of these.

Show answer
Correct Option: B
Explanation:

Ethylene production by plants is autocalalytic, i.e., a small amount of ethylene will stimulate production of its larger amounts. Thus, a few ripe fruits will initiate ripening of nearby fruits. It is, therefore, a common practice to keep few ripe bananas with unripe bananas to hasten ripening.

Ethylene promotes senescence and is found in high concentration in ripened fruits.

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

  1. True

  2. False

Show answer
Correct Option: A
Explanation:
Often considered an 'aging' hormone due to its role in accelerating such developmental processes as ripening, senescence, and abscission, the plant hormone ethylene also regulates many aspects of growth and development throughout the life cycle of the plant.

So, the correct answer is 'True'.

Artificial ripening of fruits is carried out by

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

  1. Auxin

  2. Gibberellin

  3. Abscisic acid

  4. Ethylene

Show answer
Correct Option: D
Explanation:

Ethylene is a small hydrocarbon gas as well as a phytohormone. Some fruit will produce ethylene as ripening begins. Apples and pears are examples of fruit that produce ethylene with ripening. Ethylene is responsible for the changes in texture, softening, color, and other processes involved in ripening. Ethylene gas is used commercially to ripen tomatoes, bananas, pears, and a few other fruits postharvest. 

Which hormone is used to induce ripening in banana?

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

  1. Cytokinin

  2. Ethylene

  3. ABA

  4. GA$ _{3}$

Show answer
Correct Option: B
Explanation:

Ehtylene is a simple gaseous plant growth regulator. It is synthesized in large amounts by tissues undergoing senescence and ripening of fruits. It enhances the respiration rate during ripening of fruit. This rise in rate of respiration is called as respiratory climacteric. 
Exposure of plants to ethylene causes drooping of leaves and flowers, a phenomenon known as epinasty.

Thus, the correct answer is option B.