Class 10 Science — Control and Coordination: Question Bank

A. MCQs — Choose the Correct Option

1.

Which structure receives information first in a typical neuron?

A. Axon
B. Dendrite
C. Cell body
D. Synapse

Answer: B

2.

The gap through which a signal passes between two neurons is called:

A. Axon
B. Receptor
C. Synapse
D. Dendrite

Answer: C

3.

Which sequence correctly represents the usual movement of a nerve impulse?

A. Axon → dendrite → cell body → synapse
B. Dendrite → cell body → axon → axon ending
C. Cell body → dendrite → axon → synapse
D. Dendrite → axon → cell body → synapse

Answer: B

4.

Which part of the nervous system is particularly important in a quick reflex response?

A. Cerebellum
B. Spinal cord
C. Fore-brain
D. Pituitary gland

Answer: B

5.

Which of the following is a reflex action?

A. Writing an answer
B. Walking towards a classroom
C. Pulling the hand away from a hot object
D. Choosing a book

Answer: C

6.

The brain and spinal cord together constitute the:

A. Peripheral nervous system
B. Central nervous system
C. Endocrine system
D. Sensory system

Answer: B

7.

Which brain region is primarily associated with thinking?

A. Fore-brain
B. Cerebellum
C. Medulla
D. Spinal cord

Answer: A

8.

Which part of the brain helps maintain posture and balance?

A. Fore-brain
B. Cerebellum
C. Medulla
D. Spinal cord

Answer: B

9.

Blood pressure, salivation and vomiting are examples of activities controlled by the:

A. Cerebellum
B. Medulla
C. Fore-brain
D. Dendrites

Answer: B

10.

Which system connects the central nervous system with other parts of the body?

A. Peripheral nervous system
B. Endocrine system
C. Digestive system
D. Skeletal system

Answer: A

11.

Which movement of a plant is independent of growth?

A. Bending of a shoot towards light
B. Growth of roots downwards
C. Folding of Mimosa leaves after touch
D. Growth of pollen tube towards an ovule

Answer: C

12.

The folding of leaves of a touch-me-not plant after touching is a:

A. Growth-dependent movement
B. Rapid response to a stimulus
C. Phototropic movement
D. Chemotropic movement

Answer: B

13.

In plants, rapid movement in response to touch can occur without:

A. Water
B. Hormones
C. Nervous and muscular tissue
D. Living cells

Answer: C

14.

A shoot bending towards light is an example of:

A. Geotropism
B. Hydrotropism
C. Phototropism
D. Chemotropism

Answer: C

15.

Roots generally grow downward in response to:

A. Light
B. Gravity
C. Chemicals
D. Touch

Answer: B

16.

Growth of a pollen tube towards an ovule illustrates:

A. Phototropism
B. Geotropism
C. Chemotropism
D. Hydrotropism

Answer: C

17.

Which plant hormone is particularly involved in the phototropic response described in the chapter?

A. Insulin
B. Auxin
C. Adrenaline
D. Thyroxin

Answer: B

18.

When light comes from one side, auxin accumulates more towards the:

A. Illuminated side of the shoot
B. Shady side of the shoot
C. Root tip only
D. Upper surface of the leaf

Answer: B

19.

Which hormone promotes cell division?

A. Cytokinin
B. Abscisic acid
C. Adrenaline
D. Insulin

Answer: A

20.

Which plant hormone is described as inhibiting growth?

A. Auxin
B. Gibberellin
C. Cytokinin
D. Abscisic acid

Answer: D

21.

Which hormone is released by adrenal glands during an emergency situation?

A. Insulin
B. Adrenaline
C. Thyroxin
D. Oestrogen

Answer: B

22.

Adrenaline prepares the body for emergency activity mainly by:

A. Slowing the heartbeat
B. Increasing heartbeat and breathing rate
C. Stopping blood supply to muscles
D. Increasing digestive activity

Answer: B

23.

Which hormone regulates blood glucose levels?

A. Insulin
B. Growth hormone
C. Adrenaline
D. Thyroxin

Answer: A

24.

Iodine is required by the body for the production of:

A. Insulin
B. Thyroxin
C. Adrenaline
D. Growth hormone

Answer: B

25.

Deficiency of iodine may lead to:

A. Diabetes
B. Goitre
C. Dwarfism
D. Loss of balance

Answer: B

26.

Growth hormone is secreted by the:

A. Thyroid
B. Pituitary
C. Pancreas
D. Adrenal gland

Answer: B

27.

A deficiency of growth hormone during childhood can result in:

A. Goitre
B. Dwarfism
C. Diabetes
D. Increased blood sugar

Answer: B

28.

Which hormone is associated with changes during puberty in males?

A. Testosterone
B. Insulin
C. Thyroxin
D. Cytokinin

Answer: A

29.

Which hormone is produced by the pancreas and helps regulate blood sugar?

A. Adrenaline
B. Insulin
C. Auxin
D. Oestrogen

Answer: B

30.

The mechanism that regulates the amount and timing of hormone secretion is called:

A. Reflex arc
B. Feedback mechanism
C. Synaptic transmission
D. Tropism

Answer: B

B. Assertion–Reason Questions

Choose:

A. Both A and R are true, and R correctly explains A.
B. Both A and R are true, but R does not correctly explain A.
C. A is true, but R is false.
D. A is false, but R is true.

31.

Assertion: Reflex actions are generally very rapid.
Reason: Reflex pathways can provide a response without waiting for complex conscious processing by the brain.

Answer: A

32.

Assertion: Plants can respond to stimuli despite having no nervous system.
Reason: Plants can use electrical-chemical signalling and chemical hormones.

Answer: A

33.

Assertion: The cerebellum is important for maintaining body balance.
Reason: It contributes to the precision of voluntary movements and posture.

Answer: A

34.

Assertion: A shoot bends towards light.
Reason: Auxin promotes greater elongation on the shaded side of the shoot.

Answer: A

35.

Assertion: Hormonal communication can affect many cells of the body.
Reason: Hormones can be transported through body fluids such as blood.

Answer: A

36.

Assertion: Iodised salt is recommended in the diet.
Reason: Iodine is needed to synthesise thyroxin.

Answer: A

37.

Assertion: Chemical communication is slower than electrical impulse transmission.
Reason: Chemical signals can provide communication that is steady and persistent.

Answer: B

38.

Assertion: The spinal cord has no role in reflex actions.
Reason: Reflex arcs are formed in the spinal cord.

Answer: D

C. Fill in the Blanks

39.

The basic unit of nervous tissue is the ________.

Answer: neuron

40.

The gap between two neurons is called a ________.

Answer: synapse

41.

The brain and spinal cord form the ________ nervous system.

Answer: central

42.

The ________ is mainly responsible for thinking.

Answer: fore-brain

43.

The ________ helps maintain posture and balance.

Answer: cerebellum

44.

The ________ controls several involuntary activities such as blood pressure and salivation.

Answer: medulla

45.

A rapid automatic response to a stimulus is called a ________ action.

Answer: reflex

46.

The pathway followed during a reflex response is called a ________.

Answer: reflex arc

47.

The movement of a shoot towards light is called ________.

Answer: phototropism

48.

The response of roots and shoots to gravity is called ________.

Answer: geotropism

49.

Growth of pollen tubes towards ovules is an example of ________.

Answer: chemotropism

50.

The plant hormone associated with phototropic bending is ________.

Answer: auxin

51.

________ promotes cell division in plants.

Answer: Cytokinin

52.

________ is a plant hormone that inhibits growth.

Answer: Abscisic acid

53.

The emergency hormone secreted by adrenal glands is ________.

Answer: adrenaline

54.

The thyroid gland requires ________ to synthesise thyroxin.

Answer: iodine

55.

The hormone that regulates blood sugar is ________.

Answer: insulin

56.

Insulin is produced by the ________.

Answer: pancreas

D. True or False

57.

A neuron transmits information using electrical impulses.

Answer: True

58.

The synapse is the main cell body of a neuron.

Answer: False

59.

Reflex arcs are formed in the spinal cord.

Answer: True

60.

The cerebellum is the main thinking region of the brain.

Answer: False

61.

Plants have a nervous system similar to that of animals.

Answer: False

62.

The movement of Mimosa leaves after touch is independent of growth.

Answer: True

63.

Phototropism is a response to gravity.

Answer: False

64.

Auxin can cause cells on the shaded side of a shoot to elongate.

Answer: True

65.

Adrenaline decreases the heart rate during an emergency.

Answer: False

66.

Iodine is needed for the synthesis of thyroxin.

Answer: True

67.

Insulin helps regulate blood glucose levels.

Answer: True

68.

Hormone secretion can be regulated by feedback mechanisms.

Answer: True

E. Match the Following

69.

Column A	Column B
1. Cerebellum	a. Blood sugar regulation
2. Insulin	b. Balance and posture
3. Auxin	c. Phototropic growth
4. Adrenaline	d. Emergency response

Answer: 1-b, 2-a, 3-c, 4-d

70.

Column A	Column B
1. Thyroxin	a. Cell division
2. Cytokinin	b. Metabolism
3. Abscisic acid	c. Growth inhibition
4. Growth hormone	d. Body growth

Answer: 1-b, 2-a, 3-c, 4-d

71.

Column A	Column B
1. Phototropism	a. Chemicals
2. Geotropism	b. Water
3. Hydrotropism	c. Light
4. Chemotropism	d. Gravity

Answer: 1-c, 2-d, 3-b, 4-a

F. Very Short Answer Questions

72.

What is a stimulus?

Answer: A stimulus is a change in the environment that causes an organism to produce a response.

73.

What is a receptor?

Answer: A receptor is a specialised structure, generally associated with sensory organs, that detects information from the environment.

74.

What is a neuron?

Answer: A neuron is a specialised nerve cell that conducts information through electrical impulses.

75.

What is a synapse?

Answer: It is the gap between two neurons across which information is transmitted chemically.

76.

Name the two main components of the central nervous system.

Answer: Brain and spinal cord.

77.

Name the three major regions of the brain mentioned in the chapter.

Answer: Fore-brain, mid-brain and hind-brain.

78.

Which part of the brain is responsible for maintaining balance?

Answer: Cerebellum.

79.

What protects the spinal cord?

Answer: The vertebral column.

80.

What is tropism?

Answer: Tropism is directional growth of a plant part in response to an environmental stimulus.

81.

Name the hormone that promotes cell division in plants.

Answer: Cytokinin.

82.

Name one plant hormone that inhibits growth.

Answer: Abscisic acid.

83.

Which gland secretes adrenaline?

Answer: Adrenal gland.

84.

Why is iodised salt useful?

Answer: It supplies iodine needed for synthesis of thyroxin.

85.

Which hormone regulates blood glucose?

Answer: Insulin.

G. Short Answer Questions — 2/3 Marks

86.

Explain how information travels from one neuron to another.

Answer: A stimulus produces an electrical impulse at the dendrite. The impulse passes through the cell body and axon. At the axon ending, chemicals are released into the synapse. These chemicals initiate an electrical impulse in the next neuron.

87.

Why are reflex actions important?

Answer: They provide rapid responses to potentially harmful stimuli. Reflex arcs allow the body to respond quickly without requiring complex conscious processing before the initial response.

88.

Differentiate between reflex action and voluntary action.

Answer:

Reflex action: rapid and generally automatic response to a stimulus.
Voluntary action: performed consciously after deciding what to do, such as writing or moving an object.

89.

Why does the spinal cord have an important role in reflex actions?

Answer: Reflex arcs are formed in the spinal cord, allowing signals to produce rapid responses. The information is also passed on to the brain.

90.

Why is the cerebellum important?

Answer: It coordinates voluntary movements and helps maintain posture and balance. It is important for activities requiring precision, such as cycling and picking up objects.

91.

How do plants respond to touch without having muscles?

Answer: Plants transmit information through electrical-chemical signals. Cells at the responding region change their water content, causing them to swell or shrink and alter their shape.

92.

Differentiate between growth-dependent and growth-independent plant movements.

Answer:

Growth-independent: occurs without growth; e.g. folding of Mimosa leaves after touch.
Growth-dependent: results from differential growth; e.g. bending of a shoot towards light.

93.

Why does a shoot bend towards light?

Answer: Auxin moves towards the shaded side of the shoot. It promotes greater cell elongation there, causing the shoot to bend towards the light.

94.

Differentiate between phototropism and geotropism.

Answer:

Phototropism: directional growth in response to light.
Geotropism: directional growth in response to gravity.

95.

What is the role of plant hormones?

Answer: They coordinate plant growth, development and responses to environmental stimuli.

96.

Why are hormones useful in addition to nervous coordination?

Answer: Hormones provide chemical communication that can reach a wide range of cells and can produce effects that are slower but more persistent.

97.

How does adrenaline prepare the body for emergency activity?

Answer: It increases heart rate and breathing rate, increases oxygen supply to muscles and diverts blood towards skeletal muscles by reducing blood flow to some other regions.

98.

Why is iodine important for the human body?

Answer: Iodine is necessary for synthesis of thyroxin by the thyroid gland. Thyroxin helps regulate metabolism, supporting proper growth and development.

99.

What happens when insulin is not produced in adequate amounts?

Answer: Blood glucose levels rise, which can lead to harmful effects and is associated with diabetes.

100.

What is feedback regulation of hormones? Give one example.

Answer: Feedback regulation controls hormone secretion according to the body’s requirements. For example, when blood glucose rises, insulin secretion increases; when glucose falls, insulin secretion decreases.

H. Competency / Application-Based Questions

101.

A student accidentally touches a hot vessel and immediately pulls away his hand.

a) What type of response is this?
b) Which part of the nervous system is important in this response?
c) Why is this response advantageous?

Answer:
a) Reflex action
b) Spinal cord through a reflex arc
c) It allows a rapid response to a potentially harmful stimulus.

102.

A plant kept near a window develops a shoot that bends towards the window.

a) Identify the movement.
b) Which stimulus causes it?
c) Name the hormone involved.
d) Why does bending occur?

Answer:
a) Phototropism
b) Light
c) Auxin
d) Auxin promotes greater elongation on the shaded side, causing the shoot to bend towards light.

103.

A person suddenly faces a frightening situation. Their heartbeat and breathing become faster.

a) Which hormone is involved?
b) Where is it secreted?
c) Why are these changes useful?

Answer:
a) Adrenaline
b) Adrenal glands
c) They prepare the body for rapid physical activity by increasing oxygen delivery and directing blood towards skeletal muscles.

104.

A person has insufficient iodine in their diet.

a) Which hormone may be affected?
b) Which gland produces it?
c) What disorder may result from iodine deficiency?

Answer:
a) Thyroxin
b) Thyroid gland
c) Goitre

105.

A diabetic patient is advised to take insulin.

a) Which organ produces insulin?
b) What does insulin regulate?
c) What happens when insulin is insufficient?

Answer:
a) Pancreas
b) Blood glucose level
c) Blood glucose rises.

I. Case-Based Questions

Case Study 1 — Reflex Action

A student is working in a laboratory and accidentally touches a hot object. The hand moves away almost immediately. The brain receives information about the event, but the initial response occurs rapidly through a simpler pathway.

106.

What type of response occurred?

Answer: Reflex action.

107.

What is the pathway involved called?

Answer: Reflex arc.

108.

Where is the reflex arc generally formed?

Answer: Spinal cord.

109.

Why is this pathway useful?

Answer: It enables a rapid response to a potentially dangerous stimulus.

Case Study 2 — Plant Response

A young plant is kept in a box with light entering from only one side. After some time, its shoot bends towards the light while the root grows in the opposite direction.

110.

What type of movement does the shoot show?

Answer: Phototropism.

111.

What type of response does the root show with respect to gravity?

Answer: Positive geotropism.

112.

Which hormone contributes to the shoot’s bending?

Answer: Auxin.

113.

Why does the shoot bend?

Answer: Auxin becomes concentrated towards the shaded side and promotes greater elongation there, causing the shoot to bend towards light.

Case Study 3 — Hormonal Coordination

During an emergency, the body needs to rapidly prepare different organs for physical activity. A hormone released into the bloodstream acts on several target tissues.

114.

Name the hormone.

Answer: Adrenaline.

115.

Which glands release it?

Answer: Adrenal glands.

116.

State two effects of this hormone.

Answer: It increases heart rate and breathing rate and redirects blood towards skeletal muscles.

117.

Why is hormonal coordination suitable here?

Answer: A chemical signal carried in the blood can influence several parts of the body at the same time.

J. Higher-Order Thinking Questions

118.

Why would a response to a dangerous stimulus be less useful if the body had to complete extensive conscious thinking before acting?

Answer: It could delay the response and increase the risk of harm. A reflex arc allows a quicker initial response.

119.

Why can plants show rapid movements even though they have neither muscles nor a nervous system?

Answer: They can transmit information through electrical-chemical signals, and cells can change shape by changing their water content.

120.

Why are growth movements in plants generally slower than the folding of Mimosa leaves?

Answer: Folding of Mimosa leaves involves rapid changes in cell shape and water content, whereas growth movements depend on changes in growth rates, which occur more slowly.

121.

Why can chemical communication reach cells that are not directly connected by nervous tissue?

Answer: Chemical signals such as hormones can spread through body fluids and reach target cells away from the site where they were produced.

122.

Why can’t electrical impulses alone provide all types of coordination required by a multicellular organism?

Answer: Electrical impulses mainly travel through connected nervous tissue, and nerve cells also require time to reset after transmitting an impulse. Chemical communication can provide wider and more sustained effects.

K. Long Answer Questions — 4/5 Marks

123.

Explain the structure and functioning of a neuron.

Answer points:

Dendrites receive information.
The information produces an electrical impulse.
The impulse travels through the cell body.
It continues along the axon.
Chemicals are released at the axon ending.
These cross the synapse.
They initiate an impulse in the next neuron or another target cell.

124.

Explain reflex action with the help of a suitable pathway.

Answer points:

Stimulus → receptor → sensory neuron → spinal cord → motor neuron → muscle → response

A receptor detects the stimulus.
Information travels towards the spinal cord.
A reflex connection is made there.
A motor signal reaches the muscle.
The muscle produces the response.
Information also reaches the brain.

125.

Describe the major regions of the human brain and their functions.

Answer points:

Fore-brain: thinking, interpretation of sensory information, decision-making and voluntary actions.
Mid-brain: involved in coordination of certain responses.
Hind-brain: includes structures involved in involuntary activities, posture, balance and movement coordination.
Medulla: regulates important involuntary functions.
Cerebellum: maintains posture, balance and precision of voluntary movements.

126.

Explain how plants coordinate their responses despite lacking a nervous system.

Answer points:

Plants do not have nervous or muscular tissue.
They can transmit information through electrical-chemical signals.
Cells at the responding region may change shape by changing water content.
Plants also use hormones for chemical coordination.
Hormones coordinate growth and responses.
Tropic movements occur through directional growth.

127.

Explain phototropism in plants.

Answer points:

Light acts as the stimulus.
Auxin is produced at the shoot tip.
When light comes from one side, auxin moves towards the shaded side.
Cells on that side elongate more.
Unequal growth causes the shoot to bend.
The shoot therefore grows towards the light.

128.

Explain the role of hormones in animal coordination with suitable examples.

Answer points:

Hormones are chemical signals secreted by endocrine glands.
They travel to target tissues.
Adrenaline prepares the body for emergency activity.
Thyroxin regulates metabolism.
Growth hormone regulates growth and development.
Insulin regulates blood glucose.
Hormone secretion is regulated through feedback mechanisms.

129.

Compare nervous and hormonal coordination in animals.

Nervous coordination	Hormonal coordination
Uses electrical impulses	Uses chemical hormones
Generally very rapid	Generally slower
Travels through nervous connections	Can be transported through body fluids
Usually produces rapid responses	Effects can be sustained and widespread
Closely associated with muscles and glands	Acts on specific target tissues/cells

L. Diagram-Based Questions

130.

Draw and label a neuron. Mark:

Dendrite
Cell body
Axon
Axon ending

Expected concept: Show the direction of information as:

Dendrite → Cell body → Axon → Axon ending

131.

Draw a simple reflex arc and label:

Receptor
Sensory pathway
Spinal cord
Motor pathway
Muscle

132.

Draw a labelled diagram of the human brain and identify the major regions mentioned in the chapter.

133.

Draw a plant showing phototropic response and indicate:

Direction of light
Shoot
Shaded side
Direction of bending

M. “Give Reason” Questions

134.

Why do we withdraw our hand quickly after touching a hot object?

Answer: Because a reflex arc produces a rapid protective response.

135.

Why does a shoot bend towards light?

Answer: Unequal distribution of auxin causes greater elongation on the shaded side.

136.

Why are plants capable of responding even without a nervous system?

Answer: They use electrical-chemical signalling and chemical hormones for coordination.

137.

Why does the body need feedback mechanisms for hormones?

Answer: Hormones must be released in appropriate amounts and at appropriate times; feedback helps regulate their secretion.

138.

Why is iodised salt advised?

Answer: Iodine is essential for producing thyroxin.

139.

Why does adrenaline affect several organs during an emergency?

Answer: It enters the blood and is transported to different target tissues, allowing coordinated changes throughout the body.

N. Arrange in Correct Sequence

140.

Arrange the following in the correct order for nerve transmission:

Axon, dendrite, cell body, synapse

Answer:
Dendrite → Cell body → Axon → Synapse

141.

Arrange the events of phototropism:

Shoot bends towards light
Auxin accumulates towards shaded side
Light comes from one direction
Cells on shaded side elongate more

Answer:
3 → 2 → 4 → 1

142.

Arrange the reflex pathway:

Motor neuron, receptor, muscle, spinal cord, sensory pathway

Answer:
Receptor → Sensory pathway → Spinal cord → Motor neuron → Muscle

O. One-Word / One-Term Questions

143.

Basic unit of nervous tissue — Neuron

144.

Gap between two neurons — Synapse

145.

Main thinking region — Fore-brain

146.

Brain part responsible for balance — Cerebellum

147.

Brain region controlling several involuntary functions — Medulla

148.

Directional response to light — Phototropism

149.

Directional response to gravity — Geotropism

150.

Plant hormone promoting cell division — Cytokinin

151.

Plant growth-inhibiting hormone — Abscisic acid

152.

Emergency hormone — Adrenaline

153.

Hormone regulating blood sugar — Insulin

154.

Hormone regulating metabolism — Thyroxin

155.

Hormone promoting body growth — Growth hormone