Class 10th Science Chapter 6 – Control and Coordination | Nervous System and Neurons

🧠 Control and Coordination – Nervous System and Neurons

Class 10 Science | CBSE + Foundation + Competitive Level | Animated Learning

🧠 Nervous System and Neurons

1. Control and Coordination | नियंत्रण एवं समन्वय

English:
Control and coordination allow organisms to respond appropriately to changes in their internal and external environment.

हिन्दी:
नियंत्रण एवं समन्वय वह प्रक्रिया है जिसके द्वारा जीव अपने आंतरिक तथा बाहरी पर्यावरण में होने वाले परिवर्तनों के प्रति उचित प्रतिक्रिया करते हैं।

In humans, coordination is mainly carried out by:

• Nervous System
• Endocrine System

2. Nervous System | तंत्रिका तंत्र

The nervous system receives information, processes it and produces an appropriate response.

हिन्दी:
तंत्रिका तंत्र सूचना को ग्रहण करता है, उसका विश्लेषण करता है और उचित प्रतिक्रिया उत्पन्न करता है।

Stimulus → Receptor → Sensory Neuron → CNS → Motor Neuron → Effector → Response

3. Main Divisions of Human Nervous System

Division	Main Components	Function
Central Nervous System	Brain + Spinal Cord	Processing and coordination
Peripheral Nervous System	Nerves outside CNS	Connects CNS with body parts

4. Human Nervous System – Animated Diagram

Human Brain, Spinal Cord and Nerves

5. Neuron | न्यूरॉन

English:
A neuron is the structural and functional unit of the nervous system.

हिन्दी:
न्यूरॉन तंत्रिका तंत्र की संरचनात्मक एवं क्रियात्मक इकाई है।

It is specialized to receive and transmit electrical signals.

6. Structure of Neuron | न्यूरॉन की संरचना

Animated Neuron Diagram

7. Parts of Neuron and Their Functions

Part	Function
Dendrites	Receive information/signals
Cell Body	Contains nucleus and maintains cell activities
Axon	Carries nerve impulse away from cell body
Myelin Sheath	Insulates axon and helps faster impulse transmission
Axon Terminals	Pass signal to next neuron or effector through synapse

8. Direction of Nerve Impulse | तंत्रिका आवेग की दिशा

Dendrite → Cell Body → Axon → Axon Terminal

Nerve impulse generally travels from the dendrites towards the cell body and then along the axon towards the axon terminals.

9. Synapse | सिनैप्स

A synapse is the junction between two neurons. At the synapse, the signal is transmitted from one neuron to the next through chemical substances called neurotransmitters.

Neuron → Synapse → Next Neuron

10. Reflex Action | प्रतिवर्ती क्रिया

A reflex action is a quick, automatic response to a stimulus.

Example: Pulling the hand away immediately after touching a hot object.

Stimulus → Receptor → Sensory Neuron → Spinal Cord → Motor Neuron → Muscle → Response

11. Reflex Arc | प्रतिवर्ती चाप

12. Brain | मस्तिष्क

The brain is the main coordinating centre of the nervous system. It receives information, processes it and controls appropriate responses.

Part	Main Function
Forebrain	Thinking, memory, sensory interpretation and voluntary actions
Midbrain	Coordinates certain visual and auditory responses
Hindbrain	Includes cerebellum, pons and medulla; controls balance and several involuntary functions

13. Forebrain | अग्र मस्तिष्क

Forebrain is associated with thinking, reasoning, memory, interpretation of sensory information and voluntary actions. The cerebrum forms the major part of the forebrain.

14. Cerebellum | अनुमस्तिष्क

Cerebellum helps in:

• Maintaining posture
• Maintaining balance
• Coordinating muscular movements

15. Medulla | मेडुला

The medulla is involved in several involuntary activities such as:

• Breathing
• Heartbeat
• Blood pressure regulation
• Swallowing

16. Spinal Cord | मेरुरज्जु

The spinal cord is a major part of the central nervous system. It:

• Conducts nerve impulses between brain and body.
• Participates in reflex actions.

17. Sensory and Motor Neurons

Type	Direction	Function
Sensory Neuron	Receptor → CNS	Carries sensory information
Motor Neuron	CNS → Effector	Carries commands to muscles/glands
Relay Neuron	Within CNS	Connects neurons in CNS

18. Receptors | ग्राही

Receptors are specialized structures that detect changes or stimuli in the environment. Examples:

Receptor	Stimulus
Photoreceptors	Light
Olfactory receptors	Smell
Gustatory receptors	Taste
Auditory receptors	Sound
Thermoreceptors	Temperature

19. Voluntary and Involuntary Actions

Voluntary Action	Involuntary Action
Under conscious control	Generally not under conscious control
Walking	Heartbeat
Writing	Breathing rhythm
Picking up an object	Movement of alimentary canal

20. Important Flow Charts

Stimulus → Receptor → Sensory Neuron → Brain/Spinal Cord → Motor Neuron → Effector → Response

Dendrite → Cell Body → Axon → Axon Terminal

Brain + Spinal Cord = Central Nervous System

21. MCQ – 30 Questions with Answers

Q1. The structural and functional unit of the nervous system is:

A) Neuron

B) Nephron

C) Alveolus

D) Villus

Answer: A) Neuron

Q2. Which part of a neuron receives signals?

A) Axon

B) Dendrite

C) Synapse

D) Myelin sheath

Answer: B) Dendrite

Q3. Which part carries the impulse away from the cell body?

A) Dendrite

B) Nucleus

C) Axon

D) Cell membrane

Answer: C) Axon

Q4. The central nervous system consists of:

A) Brain only

B) Spinal cord only

C) Nerves only

D) Brain and spinal cord

Answer: D) Brain and spinal cord

Q5. A reflex action is:

A) Quick and automatic response

B) Slow voluntary response

C) Hormonal response only

D) Digestive response

Answer: A) Quick and automatic response

Q6. Reflex actions are commonly coordinated through:

A) Heart

B) Spinal cord

C) Kidney

D) Liver

Answer: B) Spinal cord

Q7. The junction between two neurons is called:

A) Axon

B) Dendrite

C) Synapse

D) Receptor

Answer: C) Synapse

Q8. Which part helps in maintaining body balance?

A) Medulla

B) Cerebrum

C) Spinal cord

D) Cerebellum

Answer: D) Cerebellum

Q9. Which part of the neuron contains the nucleus?

A) Cell body

B) Axon

C) Dendrite

D) Axon terminal

Answer: A) Cell body

Q10. Sensory neurons carry impulses:

A) CNS to muscles

B) Receptors to CNS

C) Muscles to glands

D) Brain to receptors

Answer: B) Receptors to CNS

Q11. Motor neurons carry impulses:

A) Receptors to CNS

B) Skin to brain

C) CNS to effectors

D) Eye to brain only

Answer: C) CNS to effectors

Q12. Which is an example of a voluntary action?

A) Heartbeat

B) Digestion

C) Pupil adjustment

D) Writing

Answer: D) Writing

Q13. Which part of brain is mainly associated with thinking?

A) Forebrain

B) Cerebellum

C) Medulla

D) Spinal cord

Answer: A) Forebrain

Q14. Which part controls many involuntary activities?

A) Cerebrum

B) Medulla

C) Dendrite

D) Axon

Answer: B) Medulla

Q15. Which structure detects a stimulus?

A) Axon

B) Muscle

C) Receptor

D) Spinal cord

Answer: C) Receptor

Q16. Which structure protects and insulates an axon?

A) Nucleus

B) Dendrite

C) Synapse

D) Myelin sheath

Answer: D) Myelin sheath

Q17. Which of the following is an effector?

A) Muscle

B) Receptor

C) Brain

D) Spinal cord

Answer: A) Muscle

Q18. The main function of a receptor is to:

A) Digest food

B) Detect stimulus

C) Pump blood

D) Produce urine

Answer: B) Detect stimulus

Q19. Which receptor detects light?

A) Auditory receptor

B) Olfactory receptor

C) Photoreceptor

D) Thermoreceptor

Answer: C) Photoreceptor

Q20. Which receptor is associated with smell?

A) Photoreceptor

B) Thermoreceptor

C) Gustatory receptor

D) Olfactory receptor

Answer: D) Olfactory receptor

Q21. The brain and spinal cord together form:

A) Central nervous system

B) Digestive system

C) Endocrine system

D) Excretory system

Answer: A) Central nervous system

Q22. Which structure connects the CNS with body parts?

A) Nephron

B) Peripheral nerves

C) Alveoli

D) Villi

Answer: B) Peripheral nerves

Q23. Which part of neuron transmits impulses to another neuron?

A) Cell body

B) Nucleus

C) Axon terminal

D) Myelin only

Answer: C) Axon terminal

Q24. Which action is generally involuntary?

A) Writing

B) Walking

C) Running

D) Heartbeat

Answer: D) Heartbeat

Q25. What is the function of cerebellum?

A) Balance and coordination

B) Urine formation

C) Digestion

D) Blood filtration

Answer: A) Balance and coordination

Q26. Which part of brain is involved in thinking and memory?

A) Medulla

B) Forebrain

C) Spinal cord

D) Cerebellum only

Answer: B) Forebrain

Q27. A reflex arc generally includes:

A) Kidney and ureter

B) Stomach and intestine

C) Sensory neuron, CNS and motor neuron

D) Heart and lungs

Answer: C) Sensory neuron, CNS and motor neuron

Q28. Neurotransmitters are released at:

A) Nucleus

B) Dendrite

C) Cell body

D) Synapse

Answer: D) Synapse

Q29. Which statement is correct?

A) Dendrites generally receive signals

B) Axon receives all signals

C) Ureter carries nerve impulses

D) Nephron is a neuron

Answer: A) Dendrites generally receive signals

Q30. Which sequence correctly represents a simple nervous response?

A) Effector → Receptor → CNS → Stimulus

B) Stimulus → Receptor → CNS → Effector → Response

C) CNS → Stimulus → Receptor → Response

D) Response → Effector → Receptor → Stimulus

Answer: B) Stimulus → Receptor → CNS → Effector → Response

22. Subjective Questions – 30 Questions with Answers

2 Marks Q1. What is a neuron? State its function.

Answer:
Neuron is the structural and functional unit of the nervous system. It receives and transmits nerve impulses.

2 Marks Q2. What is a reflex action? Give one example.

Answer:
A reflex action is a quick and automatic response to a stimulus. Example: Pulling the hand away after touching a hot object.

2 Marks Q3. What is a synapse?

Answer:
A synapse is the junction between two neurons through which a nerve signal is transmitted from one neuron to another.

2 Marks Q4. Differentiate between sensory and motor neurons.

Sensory Neuron	Motor Neuron
Receptor → CNS	CNS → Effector
Carries sensory information	Carries commands to muscles/glands

2 Marks Q5. Name the two main parts of the central nervous system.

Answer: Brain and spinal cord.

3 Marks Q6. Explain the functions of dendrites, cell body and axon.

Dendrites: Receive signals.
Cell body: Contains nucleus and controls cell activities.
Axon: Carries nerve impulse away from cell body.

3 Marks Q7. Explain the pathway of a nerve impulse through a neuron.

The impulse is generally received by dendrites, passes through the cell body and travels along the axon to the axon terminal.

3 Marks Q8. What is a reflex arc? Write its main components.

A reflex arc is the pathway followed by a nerve impulse during a reflex action.

Main components: Receptor → Sensory neuron → CNS → Motor neuron → Effector.

3 Marks Q9. Write three functions of the spinal cord.

1. Conducts impulses between brain and body.
2. Participates in reflex actions.
3. Connects different parts of the nervous system.

3 Marks Q10. What are receptors? Give two examples.

Receptors are specialized structures that detect stimuli.

Examples: Photoreceptors detect light and olfactory receptors detect smell.

4 Marks Q11. Describe the structure of a neuron with a labelled diagram.

A neuron consists of dendrites, cell body, nucleus, axon and axon terminals. Dendrites receive signals and axon carries impulses away from the cell body.

4 Marks Q12. Explain reflex action with the help of a reflex arc.

A stimulus is detected by a receptor. The sensory neuron carries the impulse to the CNS. The CNS processes the information and sends a command through a motor neuron. The effector produces a quick response.

4 Marks Q13. Differentiate between voluntary and involuntary actions.

Voluntary	Involuntary
Under conscious control	Generally automatic
Walking, writing	Heartbeat, digestion

4 Marks Q14. Explain the functions of forebrain, cerebellum and medulla.

Forebrain: Thinking, memory and voluntary actions.
Cerebellum: Balance and coordination of muscles.
Medulla: Controls several involuntary activities.

4 Marks Q15. Differentiate between central and peripheral nervous systems.

Central Nervous System: Brain and spinal cord; main processing centre.

Peripheral Nervous System: Nerves outside CNS; connects CNS with body parts.

5 Marks Q16. Explain the structure and function of a neuron.

A neuron has dendrites, cell body, nucleus, axon and axon terminals.

Dendrites receive information. The cell body maintains cellular activities. The axon carries impulses away from the cell body. Axon terminals transmit signals to the next neuron or effector.

5 Marks Q17. Explain the transmission of a nerve impulse from one neuron to another.

The impulse travels along the neuron to the axon terminal. At the synapse, chemicals called neurotransmitters are released. These chemicals cross the synaptic gap and stimulate the next neuron, initiating a new electrical signal.

5 Marks Q18. Explain the role of brain in control and coordination.

The brain receives sensory information and processes it. It controls voluntary activities such as movement and thinking. Different regions also control balance, coordination and involuntary activities such as breathing and heartbeat.

5 Marks Q19. Explain the reflex arc with a suitable example.

When a person touches a hot object, receptors in the skin detect the heat. The sensory neuron carries the impulse to the spinal cord. A motor neuron carries the response to muscles. The muscles contract and pull the hand away.

5 Marks Q20. Explain the role of receptors in control and coordination.

Receptors detect specific stimuli. They convert the stimulus into nerve signals which are carried through sensory neurons to the central nervous system. Examples include photoreceptors for light and olfactory receptors for smell.

6 Marks Q21. Explain the human nervous system with its major divisions.

The human nervous system consists of the central and peripheral nervous systems.

Central Nervous System: It consists of brain and spinal cord and acts as the main processing and coordination centre.

Peripheral Nervous System: It consists of nerves outside the CNS and connects the CNS with receptors and effectors.

Together they receive information, process it and coordinate responses.

6 Marks Q22. Draw a labelled diagram of a neuron and explain the function of its parts.

Important labels:

Dendrites, Cell Body, Nucleus, Axon, Myelin Sheath and Axon Terminals.

Dendrites receive signals. Cell body contains the nucleus. Axon carries impulses away from the cell body. Myelin sheath provides insulation. Axon terminals pass signals to another neuron or effector.

6 Marks Q23. Explain reflex action and reflex arc in detail.

A reflex action is a quick, automatic response to a stimulus.

The pathway is:

Stimulus → Receptor → Sensory Neuron → Spinal Cord → Motor Neuron → Effector → Response

The reflex arc allows a rapid response and helps protect the body from harmful stimuli.

6 Marks Q24. Describe the main parts of the brain and their functions.

Forebrain: Thinking, reasoning, memory, sensory interpretation and voluntary actions.

Midbrain: Coordinates certain visual and auditory responses.

Hindbrain: Includes cerebellum, pons and medulla. It helps in balance, coordination and several involuntary functions.

6 Marks Q25. Explain how a nerve impulse travels through a neuron and across a synapse.

The impulse is received by dendrites. It passes through the cell body and travels along the axon. At the axon terminal, neurotransmitters are released into the synaptic gap. They stimulate the next neuron and transmit the signal.

6 Marks Q26. Explain the difference between sensory, relay and motor neurons.

Sensory neuron: Carries impulses from receptors to the CNS.

Relay neuron: Connects neurons within the CNS and helps in processing.

Motor neuron: Carries impulses from CNS to muscles or glands.

6 Marks Q27. Explain how the nervous system helps in control and coordination.

The nervous system detects changes through receptors. Sensory neurons carry information to the CNS. The brain or spinal cord processes the information. Motor neurons then carry instructions to effectors such as muscles or glands. The effector produces an appropriate response.

6 Marks Q28. Explain the functions of cerebrum, cerebellum and medulla.

Cerebrum: Thinking, memory, intelligence, sensory interpretation and voluntary actions.

Cerebellum: Maintains posture, balance and coordination of muscular movements.

Medulla: Controls several involuntary functions including breathing and heartbeat.

6 Marks Q29. Explain why reflex actions are generally faster than conscious responses.

In many reflex actions, the response is coordinated through the spinal cord without waiting for conscious processing by the brain. The shorter pathway allows the body to respond rapidly to potentially harmful stimuli. The brain is informed about the event as well.

6 Marks Q30. Draw and explain a labelled diagram of the human nervous system.

The diagram should include:

• Brain
• Spinal cord
• Peripheral nerves

The brain and spinal cord form the central nervous system. Peripheral nerves connect the CNS with receptors and effectors throughout the body.

23. HOTS / Competency Based Questions

HOTS Q1. Why does a person immediately withdraw the hand after touching a hot object?

Because the stimulus produces a reflex action through a reflex arc, allowing a rapid protective response.

HOTS Q2. Why is the spinal cord important even though the brain is the main control centre?

The spinal cord connects the brain with the body and also coordinates many rapid reflex actions.

HOTS Q3. What would happen if the sensory neuron were damaged?

Sensory information from the affected receptor would not be properly transmitted to the CNS, so the corresponding sensation and response could be impaired.

24. CBSE Golden Points | परीक्षा के लिए महत्वपूर्ण बिंदु

✔ Neuron = Structural and functional unit of nervous system.

✔ Dendrites receive signals.

✔ Axon carries impulse away from cell body.

✔ Synapse is the junction between neurons.

✔ CNS = Brain + Spinal Cord.

✔ Reflex action is quick and automatic.

✔ Spinal cord participates in reflex actions.

✔ Cerebellum controls balance and muscular coordination.

✔ Forebrain is associated with thinking and voluntary actions.

✔ Medulla controls several involuntary activities.

✔ Sensory neuron: Receptor → CNS.

✔ Motor neuron: CNS → Effector.

✔ Receptors detect stimuli.

✔ Myelin sheath provides insulation around the axon.

25. Diagram Labelling Practice

Diagram	Important Labels
Neuron	Dendrites, Cell Body, Nucleus, Axon, Myelin Sheath, Axon Terminals
Human Nervous System	Brain, Spinal Cord, Peripheral Nerves
Reflex Arc	Receptor, Sensory Neuron, Spinal Cord, Motor Neuron, Effector
Brain	Forebrain, Midbrain, Hindbrain, Cerebellum, Medulla

26. Quick Revision

Neuron = Structural + Functional Unit of Nervous System

Dendrite → Cell Body → Axon → Axon Terminal

CNS = Brain + Spinal Cord

Stimulus → Receptor → Sensory Neuron → CNS → Motor Neuron → Effector → Response

Reflex Action = Quick + Automatic + Protective Response

One-Line Revision:

मानव nervous system receptors से information प्राप्त करता है, neurons द्वारा उसे CNS तक पहुँचाता है और brain/spinal cord के coordination के बाद motor neurons effectors तक response पहुँचाते हैं।