Tag: biology

Quizzes (1160) Questions (12174)

Questions Related to biology

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

The deteriorative proceses in plants, that naturally terminates their functional life, are collectively called as ...............

  1. Wilting

  2. Abscission

  3. Plasmolysis

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

Senescence refers to a number of controlled processes which finally culminate in death of the plant part. Senescence is a controlled process and is generally responsible for conservation of precious part nutrients like nitrogen and phosphorous. The senescing plant part is separated from plant due to formation of an abscission layer which finally separated the plant part.

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

Which one of the following is a naturally occurring growth inhibitor?

  1. IAA

  2. ABA

  3. NAA

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

Abscisic acid is the plant growth hormone which is responsible for inhibiting growth. This is the natural growth inhibitor which is produced in the plants. The hormone causes inhibition in the growth of the roots and shoots. The hormone also causes abscission which is the falling of the leaves, fruits and flowers. The hormone suppresses all the processes in the plants during unfavourable conditions. 

Thus, the correct answer is option D. 

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

Which one of the following triggers the ripening of fruits? 

  1. Ethylene

  2. Indoleacetic acid

  3. Gibberellic acid

  4. Kinetin
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ethylene is the gaseous hormone that stimulates growth and development of floral organs and promotes fruit ripening. It does so by causing softening of fruit due to enzymatic breakdown of cell walls, starch hydrolysis, sugar accumulation and disappearance of organic acids and phenolic compounds. Thus, option A is correct. 

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

_______ is naturally occurring growth inhibitor.

  1. Ethylene

  2. Abscissic acid

  3. Cytokinin

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

During drought and other unfavorable climatic conditions it is very important to maintain viability of the seeds. Abscissic acid is released during this condition and interacts with growth hormone in order to inhibit the growth of plant.

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

Which hormone is responsible for spoiling the whole barrel containing one bad apple?

  1. Ethylene gas

  2. Abscisic acid

  3. Auxin

  4. Gibberellins

  5. Cytokinins
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ethylene is gaseous hormone promotes fruit ripening and abscission. It diffuses from the rotten apple to other apples in the barrel and thereby causing spoilage of the whole barrel. ABA, auxins, gibberellins and cytokines are not gaseous hormones and therefore can not diffuse from one fruit to other. Thus, the correct answer is A.

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

"One bad apple spoils the whole barrel" because of

  1. Ethylene gas

  2. Abscisic acid

  3. Auxin

  4. Gibberellins

  5. Cytokinins
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ethylene gas is the plant hormone that promotes fruit ripening and rotting. It also controls flower wilting and leaf fall by stimulating the conversion of starch and acid to sugars. Therefore, it is said that one bad apple will spoil the whole barrel because of ethylene gas.

Therefore, the correct answer is option A.

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

Presence of ethylene gas causes fruits to ripen. As fruit ripens, it produces increasing amounts of ethylene.

This is an example of

  1. Positive feedback

  2. Negative feedback

  3. Homeostasis

  4. Endocrine regulation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

ethylene gas is an aging hormone used for fruit ripening but may also cause the plant to die. Ethylene gas is released when the plant is damaged mechanically or physically.

So the correct option is 'Positive feedback.'

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

In the fall, the leaves of deciduous trees change color, fall off and die. This shedding of leaves is Mated by which of the following plant hormones? 

  1. auxin

  2. gibberellin

  3. abscisic acid

  4. cytokinin

  5. ethylene
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A. Auxin plays role in cell elongation, apical dominance, root initiation, prevention of abscission, induction of parthenocarpy and also used as herbicide.
B. Gibberellin plays role in stem elongation, seed germination, breaking dormancy, elongation of internodes and inducing parthenocarpy.
C. Abscisic acid or ABA is known as stress hormone and induces stomatal closure, provides defence against salt and cold stress, induces dormancy, causes geotropism in roots and abscission of leaves, flowers and fruits.
D. Cytokinin plays role in promoting cell division and organ formation, delay in senescence, promoting lateral bud development in dicots, cell expansion in cotyledons leaves, promoting chloroplast development and chlorophyll synthesis.
E. Ethylene is a gaseous hormone and causes ripening of fruit.
So, the correct answer is 'Abscisic acid'.
Multiple choice biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

Artificial ripening of which of the following fruits is useless ...............

  1. Mango

  2. Banana

  3. Guava

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

Artificial ripening of pomegranate and coconut is useless. It is not useful in these fruits because of their inner structure. In other fruits, calcium carbide is used for artificial ripening.