PLANT GROWTH AND DEVELOPMENT

2010 March

1. Choose the appropriate function from the bracket and fill up the blanks against each plant hormone in the table. (2)

(Ripening of fruits, helps to overcome apical dominance, increase in length of stem in sugarcane, induction of parthenocarpy)

A Plant hormone	B Function of the hormone
Auxin	…………………………
Gibberellins	…………………………
Cytokinin	…………………………
Ethylene	…………………………

2. Grasses are capable of regeneration in spite of continuous grazing by cattle. Suggest the reason for it. (1)

3. Some wheat varieties are sown in the spring season and some are sown in the autumn season. Mention the physiological phenomenon responsible for it.

2010 September

1. Comment on the following statements: (3)

a. Absicisic acid is also known as stress hormone.
b. There are hormones promoting apical dominance and those acting against apical dominance.

2011 March

1. Match the following: (3)

A	B	C
Auxins	Regain the capacity of division	Ripening of fruit
Gibberellin	Stress hormone	Does not occur naturally
Cytokinin	Gas	Stomatal movement
Dedifferentiation	Kinetin	Delay senescence
ABA	IAA	Cork cambium
Ethylene	GA₃	Apical growth

2011 October (Improvement)

1. Label the phases of growth in the given growth curve. (1½)

2. Removal of terminal buds is a usual practice in tea plantation. Explain the reason. Name a synthetic auxin. (1½)

2012 March

1. Given below is the growth curve of a plant. Observe it and answer the questions.

a. Name the growth curve. (½)
b. Label A and C phases of growth in the growth curve. (1)
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 hormone responsible for this phenomenon. (1½)

2012 September (Improvement)

1. Suggest the reason for the following: (2)

a. Farmers remove leaves of banana plants before planting.

2. Artificial phytohormones are widely used in agriculture. (2)

a. Name any two artificial phytohormones.
b. Mention their importance in agriculture.

2013 March

1. Analyze the given statements and correct them with respect to the underlined words.

a. The site of perception of light by a plant for a photoperiodic response is a flower. (1)

2. Match the following: (4 x ½ = 2)

a) Auxin	i. Fruit ripening
b) Gibberellins	ii. Stomatal closure
c) Cytokinins	iii. Root initiation
d) Ethylene	iv. Bolting
	v. Overcome apical dominance

2013 September-October (Improvement)

1. Given are certain physiological effects. Name the plant hormone responsible for it. (3)

a. Increase in stem length
b. Apical dominance
c. Closure of stomata
d. Ripening of fruits
e. Bolting
f. Active cell division

2014 March

1. By observing the relationship of the first pair, fill in the blanks of the second pair.

a. F.W. Went: Auxin E. Kurosawa: ………… (½)
b. Auxins: Apical dominance
………………: Overcome Apical dominance (½)

2. Which one of the plant growth regulators would you use if you are asked to do the following processes?

a. Induce parthenocarpy
b. Quickly ripen a fruit
c. Induce immediate stomatal closure in leaves
d. To increase the length of grape stalks. (4 x ½ = 2)

2014 August (Improvement)

1. 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. (1)

2. Observe the graph:

The graph represents the different phases of growth. Name the growth curve and identify the different phases of growth represented in the diagrams as (a), (b) and (c). (2)

2015 March

1. Apical dominance and bolting are two physiological phenomena shown by plants due to the activity of two growth regulators.

i) The growth regulators concerned are:

a) Apical dominance: …………
b) Bolting ……….. (1)

ii) Distinguish between the two phenomena. (2)

2. In most of the plants, roots are meant for absorption and fixation. But there are exceptions to these functions. Justify the statement citing at least three examples. (3)

The main function of most of the stems is spreading out branches, bearing leaves, flowers and fruits and the conduction of materials. But there are exceptions to this. Justify the statement citing at least three examples.

2015 September (Improvement)

1. Match the following: (3x1=3)

A	B
a) Auxin	i. Delay of leaf senescence
b) Gibberellin	ii. Promotes senescence
c) Cytokinins	iii. Promotes bolting
	iv. Apical dominance

2016 March

1. a) Identify the odd one from the given list of plant growth regulators.

i) ABB ii) NAA iii) IAA iv) IBA

b) List some physiological responses of gibberellins in plants. (3)

2017 March

1. Who among the following scientists is related with the identiﬁcation of cytokinins?

a) E. Kurosawa
b) F. Skoog
c) C. Darwin
d) F.W. Went (1)

2. Write any four agricultural applications of ethylene. (2)

2017 July (Improvement)

1. An enzyme present in plants, which shows carboxylation and oxygenation activity. Identify the enzyme. (1)

2. Ethylene is a gaseous hormone. Describe its four different actions in plants. (2)

2018 March

1. Write a note on the phenomenon plasticity exhibited by plants with an example.

2. Plant growth regulators can be employed for various agricultural and horticultural practices. Identify the growth regulators that can be used following purposes.

a) To have weed free lawns
b) To increase sugarcane length
c) Fruit set in pineapples
d) Rooting in stem cuttings
e) Inhibiting seed germination
f) To promote female flowers in cucumber

Plant Growth and Development | Previous year Questions | Class 11

PLANT GROWTH AND DEVELOPMENT