Plus One Botany Chapter Wise Previous Questions Chapter 11 Plant Growth and Development

Kerala Plus One Botany Chapter Wise Previous Questions and Answers Chapter 11 Plant Growth and Development

Question 1.
Choose the appropriate function from the bracket and fill up the blanks against each plant hormone in the table.
(Ripening of fruits, helps to overcome apical domi-nance, increase in length of stem in sugarcane, in-duction of parthenocarpy). (MARCH-2010)
Answer:

Up Auxin — Induction of parthenocarpy
Gibberellin — Increase the stem length of sugarcane
Cytokinin — Helps to overcome apical dominance
Ethylene — Ripening of fruits

Question 2.
Some wheat varieties are sown in the spring season and some are sown in the autumn season. Mention the physiogloical phenomenon responsible for it. (MARCH-2010)
Answer:
Vernalisation

Question 3.
Comment on the following statements: [SAY -2010]
(a) Abscisic acid is also known as stress hormone.
(b) There are hormones promoting apical dominance and those acting against apical dominance.
Answer:
(a) ABA slimulates closure of stomata / increases tolerance of plants to various kinds of stress.
(b) Apical dominance – Auxin / Ethylene. Cytokinin act against apical dominance.

Question 4.
Match the following [MARCH – 2011]

Answer:

Question 5.
Label the phases of growth in the given growth curve. [SAY – 2011]

Answer:
Lag phase, Log phase and stationary phase

Question 6.
Removal of terminal buds is a usual practice in tea plantation. Explain the reason. Name a synthetic auxin. [MARCH – 2012]
Answer:
Removal of terminal bud promotes axillary / lateral branching
Synthetic auxin – 2, 4 – Dichlorophenoxy acetic acid

Question 7.
Given below is the growth curve of a plant. Observe it and answer the questions. [MARCH – 2012]

(a) Name the growth curve.
(b) Label A and C phases of growth in the growth curve.
(c) When the tip of cassava plant is lost, a number of lateral branches grow from the nodes below. Explain this phenomenon and specify the hor¬mone responsible for this phenomenon.
You can select either 16th or 17th question and answer that question only.
Answer:
(a) Sigmoid curve
(b) A – Lag phase
C- Stationary phase
(c) Removal of apical dominance. The cytokinin pro-motes the growth of latral buds.

Question 8.
Based on the relationship fill in the blanks. [Say -2010]
Cell division : Cytokinin Bolting : ……………
Answer:
Gibberellins

Question 9.
Suggest the correct scientific term for the following: [MARCH – 2012]
Flowering on exposure to low temperature
Answer:
(a) Vernalisation or Chilling treatement

Question 10.
Artificial phytohormones are widely used in agriculture. [SAY – 2012]
(a) Name any two artificial phytohormones.
(b) Mention their importance in agriculture.
Answer:
(a) 2, 4-D, NAA
2, 4 – D – Used as weedicide.
NAA – Used for flower initiation in pineapple or initiation rooting in stem cutting.

Question 11.
Match the following: [MARCH – 2013]

Answer:
(a) – iii (b) – iv, (c) – v, (d) – i

Question 12.
Given are certain physiological effects. Name the plant hormone responsible for it. [SAY – 2013]
(a) Increase in stem length.
(b) Apical dominance
(c) Closure of stomata
(d) Ripening of fruits
(e) Bolting
(f) Active cell division
Answer:
(a) Increase stem length-GA₃
(b) Apical dominance—Auxin
(c) Closure of stomata—ABA
(d) Ripening of fruits—Ethylene
(e) Bolting—GA₃
(f) Active cell division -Cytokinin

Question 13.
Which one of the plant growth regulators would you use if you are asked to do the following processes? [MARCH – 2014]
(a) Induce parthenocarpy
(b) Quickly ripen a fruit
(c) Induce immediate stomatal closure in leaves
(d) To increase the length of grape stalks.
Answer:
(a) Auxin
(b) ethylene
(c) Abscissic acid
(d) Gibberellins

Question 14.
In certain plants, a tolerance to various kinds of stresses such as severe drought can be overcome by the production of a hormone. Name this hormone. [SAY – 2014]
Answer:
Abscissic acid

Question 15.
Observe the graph [MARCH – 2015]
Answer:

The graph represents the different phases of growth. Name the growth curve and identify the different phases of growth represented in the diagram as (a) , (b), and (c).
Answer:
(a) Lag phase (b) Log phase (c) Stationary phase

Question 16.
Apcial dominance and bolting are two physiological phenomena shown by plants due to the activity of two growth regulators. [MARCH – 2015]
(i) The growth regulators concerned are: …………….
(a) Apical dominance : …………….
(b) Bolting : ………………
(ii) Distinguish between the two phenomena.
Answer:
(i) (a) apical dominance -auxin
(b) Bolting- Gibberellin
(ii) Apical dominance – The presence of auxin in shoot apex promote the growth of apical buds and inhibit the growth of lateral buds
Bolting- It is the internodal elongation just prior to flowering.

Question 17.
Match the following : [SAY – 2015]
Answer:

Answer:
Auxin – apical dominance
Gibberellins – promotes bolting
Cytokinin – delay of leaf senescence
OR
(a) Identify the odd one from the given list of plant growth regulators.
(i) ABB
(ii) NAA
(iii) IAA
( iv) I BA
(b) List some physiological responses of gibberellins in plants.
Answer:
(a) ABA :
(b)

• GA₃ causes an increase in the length of grapes stalks.
• Gibberellins, cause fruits like apple to elongate and improve its shape
• They delay senescence. Hence the fruits are keeping as fresh.
• GA₃ is used to speed up the malting process in brewing industry.

Question 18.
Auxin and Gibberellin are two important growth hormones that control plant growth. Write any two important functions of each of these hormones. [SAY – 2016]
Answer:
Maximum

• It promote apical dominance
• It promote root initiation
• It prevents premature fruit and leaf fall
• It promote abscission of old mature leaves and fruits

Gibberellin

• It promote Bolting
• It delays senescence
• It promote stem elongation
• It speed up malting process in brewing industry

Question 19.
Who among the following scientists is related with the identification of cytokinins? [March -2017]
(a) E. Kurosawa
(b) F. Skoog
(c) C. Darwin
(d) F.W. Went
Answer:
(b) F. Skoog

Plus One Botany Chapter Wise Previous Year Questions and Answer