Tag: plant growth

Questions Related to plant growth

On the basis of corelation, find the correct options from columns. 

Column I Column-II Column III
I. Foolish plant (p) Volatile hormone (i) Induces dormancy
II. Induces senescence  (q) GA(r) Zeatin (ii) Ripen fruits(iii) Usually sterile plant
biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

  1. I - p - ii , II - r- i

  2. I - r - iii , II - q- iii

  3. I - q - iii , II - p- ii

  4. I - q - i , II - r- ii

Show answer
Correct Option: C
Explanation:

GA is Gibberillic acid a plant hormone which causes foolish seedling disease in which plants grow really tall because of the internodal growth. Gibberillic acid has been reported to induce pollen sterility in many plants like sunflower, rice etc. Ethylene is a volatile hormone which induces senescence and fruit ripening. Thus, the correct option is C. 

Shedding of leaves, flowers and fruits due to change in hormone balance in plants is

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

  1. Senescence

  2. Abscission

  3. Photoperiodism

  4. Vernalisation

Show answer
Correct Option: B
Explanation:

Senescence is the process by which cells stop dividing and growth is arrested without undergoing cell death. It is also called as ageing. Abscission is also called as fall. Shedding of leaves, flowers or fruits due to change in hormone balance in plant is called as abscission. Photoperiodism is the phenomenon in which formation of flowers in plants depends on the relative length of dark or light periods. Vernalization is the process by which plant can be induced to flower by exposing it to the prolonged period of low temperature or cold. 

Thus, the correct answer is option B.

Abscisic acid causes

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

  1. Faster leaf fall

  2. Dormancy of buds and seeds

  3. Retardation of growth

  4. All the above

Show answer
Correct Option: D
Explanation:

Abscisic acid is a plant hormone. It is also called as stress hormone as it protects the plants under stress condtion. During unfavourable environmental condition, it causes bud and seed dormancy. Only under favourable condition, the seed dormancy is broken. It also causes retardation of growth. Also, it causes abscission or fall of leaves and hence, the name given.

Thus, the correct answer is option D.

A natural growth regulator is

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

  1. 2, 4-D

  2. Benzaldehyde

  3. NAA

  4. Ethylene

Show answer
Correct Option: D
Explanation:

A 2 ,4-D is an synthetic type of auxin, a plant hormone. It acts as weedicide as it kills weeds. Benzaldehyde is a synthetic growth regulator. It acts as pesticide. NAA is a synthetic type of auxin, a plant hormone. It acts as synthetic growth regulator. It acts as rooting agent. Ethylene is a gaseous plant hormone. It acts as natural growth regulator. It hastens the ripening of fruits. 

Thus, the correct answer is option D.

Match the column I with column II

   Column I    Column II
 A.  Ethylene  1.  Pigment
 B.  Cytokinin  2.  Growth inhibitor
 C.  Phytochrome  3.  Flowering hormone
 D.  Florigen  4.  Zeatin

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

  1. A- 4, B- 3, C- 2, D- 1

  2. A- 3, B- 4, C- 2, D- 1

  3. A- 2, B- 4, C- 1, D- 3

  4. A- 2, B- 1, C- 3, D- 4

Show answer
Correct Option: C
Explanation:
Column I Column II
Ethylene Growth inhibitor
Cytokinin  Zeatin
 Phytochrome  Pigment
 Florigen  Flowering hormone

Hence, correct option is C.

Leaf fall occurs in a tree when there is increase in concentration of

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

  1. Gibberellin

  2. Cytokinin

  3. Auxin

  4. ethylene

Show answer
Correct Option: D
Explanation:

Abscisic acid is a plant hormone. It is involved in various physiological processes of plant. It promotes abscission of leaves and hence the name given. Its concentration increases as plant ages and ultimately results in the leaf fall. It is involved in the ageing process of plant.

Thus, the correct answer is option D.

Which of the following plant hormones reduces transpiration rate by inducing stomatal closure

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

  1. Ethylene

  2. Gibberellin

  3. ABA

  4. Cytokinin

Show answer
Correct Option: C
Explanation:

ABA (abscisic acid) is a plant hormone. It is also called as stress hormone as its concentration increases during stress condition. During adverse environmental conditions like drought, it induces stomatal closure. This results in reduced transpiration rate during water stress condition.

Thus, the correct answer is option C.

Consider the following statements.
a. Copper is present in Cytochrome oxidase
b. Pantothenic acid is the precursor of Coenzyme A
c. Thiamine pyrophosphate is the prosthetic group in decarboxylases
d. Zinc is present in RNA and DNA polymerases
Which of these statements are correct?

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

  1. $1$ and $2$

  2. $2, 3$ and $4$

  3. $1, 2, 3$ and $4$

  4. $1, 3$ and $4$

Show answer
Correct Option: A

Match List I with List II and select the correct answer.

List-I(Name of chemical substance) List-II(Chemical structure)
a. Indoleacetic acid $1$. Benzene
b. a-naphthalene acetic acid $2$. Circular
c. Indolepyruvic acid $3$. Chain
d. Indolebutyric acid $4$. Anoymous
biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

  1. A-$2$, B-$3$, C-$4$, D-$1$

  2. A-$1$, B-$4$, C-$3$, D-$2$

  3. A-$2$, B-$4$, C-$3$, D-$1$

  4. A-$1$, B-$3$, C-$4$, D-$2$

Show answer
Correct Option: A

Which one of the following is a synthetic cytokinin?

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

  1. Ethylene-diaminetetraacetic acid

  2. Carboboenzoxyglylalanine

  3. $6$-furfurylaminopurine

  4. $2, 4$-$5$ trichlorophenoxypropionic acid

Show answer
Correct Option: A