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

🧠 Control and Coordination

Nervous System – Central and Peripheral Nervous System | Class 10 Science | CBSE + Foundation + Competitive

🧠 Central and Peripheral Nervous System

1. Nervous System – तंत्रिका तंत्र

The nervous system is a network of specialised cells, tissues and organs that receives information, processes it and coordinates responses.

तंत्रिका तंत्र शरीर में सूचनाओं को ग्रहण करने, उनका विश्लेषण करने तथा उचित प्रतिक्रिया का समन्वय करने वाला तंत्र है।

It helps the body respond to changes in both the external and internal environment.

Main structural divisions:

• Central Nervous System (CNS) – Brain + Spinal Cord
• Peripheral Nervous System (PNS) – Nerves outside the brain and spinal cord

2. Complete Organisation of Nervous System

Animated Nervous System Organisation

CNS = Brain + Spinal Cord
PNS = Nerves connecting CNS with the rest of the body

3. Central Nervous System (CNS) – केंद्रीय तंत्रिका तंत्र

The Central Nervous System consists of:

Brain Spinal Cord

CNS acts as the major processing and coordination centre of the nervous system.

Functions:

• Receives sensory information.
• Processes and interprets information.
• Coordinates responses.
• Controls voluntary activities.
• Participates in regulation of involuntary activities.
• Coordinates many reflex actions through the spinal cord.

4. Brain – मस्तिष्क

The brain is the main control centre of the nervous system.

Major regions commonly studied at Class 10 level include:

• Forebrain – thinking, reasoning, memory and voluntary activities.
• Midbrain – certain visual and auditory reflexes.
• Hindbrain – includes cerebellum, pons and medulla.

5. Spinal Cord – मेरुरज्जु

The spinal cord is a long, delicate structure extending from the brain and protected by the vertebral column.

Functions:

• Carries nerve impulses between brain and body.
• Acts as an important pathway for sensory and motor information.
• Coordinates many reflex actions.

6. Peripheral Nervous System (PNS)

The Peripheral Nervous System consists mainly of nerves and associated structures outside the brain and spinal cord.

It connects the CNS with sensory receptors, muscles and glands throughout the body.

Basic functional divisions:

• Sensory (afferent) pathways: Carry information towards CNS.
• Motor (efferent) pathways: Carry commands away from CNS.

7. Functional Organisation of PNS

PNS – Sensory and Motor Pathways

8. Sensory / Afferent Pathway

Afferent pathways carry information towards the CNS.

Example: If a person touches a hot object, receptors in the skin detect the harmful stimulus. Sensory neurons carry information towards the CNS.

Receptor → Sensory Neuron → CNS

9. Motor / Efferent Pathway

Efferent pathways carry commands away from the CNS towards effectors.

Effectors include muscles and glands.

CNS → Motor Neuron → Effector

10. Somatic and Autonomic Functional Control

At a functional level, motor control is often described as:

Somatic nervous system:
Associated mainly with conscious control of skeletal muscles.

Autonomic nervous system:
Regulates many involuntary functions of internal organs and glands.

Note: These are functional descriptions of the peripheral nervous system and are useful for higher-level understanding.

11. CNS vs PNS

Central Nervous System (CNS)	Peripheral Nervous System (PNS)
Consists of brain and spinal cord.	Consists mainly of nerves outside brain and spinal cord.
Main processing and coordination centre.	Connects CNS with the rest of the body.
Interprets and integrates information.	Carries sensory and motor information.
Brain is protected by skull.	Nerves extend throughout body.
Spinal cord is protected by vertebral column.	Includes sensory and motor nerve pathways.

12. Sensory and Motor Neurons

Feature	Sensory Neuron	Motor Neuron
Direction	Receptor → CNS	CNS → Effector
Function	Carries sensory information.	Carries motor commands.
Pathway	Afferent	Efferent
Example	Heat detected by skin.	Muscle contracts to withdraw hand.

13. Nervous System and Reflex Action

The nervous system allows rapid responses through neural pathways.

In a typical withdrawal reflex:

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

The spinal cord can coordinate the immediate response, while information can also reach the brain so that the person becomes consciously aware of the stimulus.

14. Importance of CNS and PNS

CNS

Processing and coordination

PNS

Communication between CNS and body

Sensory Pathway

Information → CNS

Motor Pathway

CNS → Effector

15. 30 MCQs – Multiple Choice Questions

Q1. The central nervous system consists of:

A) Brain and spinal cord

B) Nerves and muscles

C) Brain and muscles

D) Spinal cord and glands

Answer: A

Q2. PNS mainly consists of:

A) Brain only

B) Spinal cord only

C) Nerves outside the CNS

D) Skull

Answer: C

Q3. Which is the main processing centre of the nervous system?

A) PNS

B) CNS

C) Muscles

D) Glands

Answer: B

Q4. Which pathway carries information towards the CNS?

A) Efferent

B) Motor

C) Afferent

D) Secretory

Answer: C

Q5. Which pathway carries commands away from CNS?

A) Sensory

B) Afferent

C) Receptor

D) Efferent

Answer: D

Q6. Which structure is part of CNS?

A) Spinal cord

B) Peripheral nerve

C) Receptor

D) Muscle

Answer: A

Q7. Which structure connects the CNS with the body?

A) PNS

B) Skull

C) Cerebrum

D) Cerebellum

Answer: A

Q8. Sensory neurons carry impulses from:

A) CNS to muscles

B) Receptors to CNS

C) Muscles to glands

D) Brain to spinal cord only

Answer: B

Q9. Motor neurons carry impulses from:

A) Receptors to CNS

B) CNS to effectors

C) Skin to brain only

D) Muscles to receptors

Answer: B

Q10. Which protects the spinal cord?

A) Skull

B) Rib cage

C) Vertebral column

D) Pelvis

Answer: C

Q11. Which two structures form CNS?

A) Brain and spinal cord

B) Brain and nerves

C) Nerves and muscles

D) Spinal cord and glands

Answer: A

Q12. Which is NOT a component of CNS?

A) Brain

B) Spinal cord

C) Peripheral nerve

D) None of these

Answer: C

Q13. The spinal cord is important in:

A) Reflex actions

B) Digestion only

C) Blood filtration

D) Photosynthesis

Answer: A

Q14. Afferent means:

A) Away from CNS

B) Towards CNS

C) Towards muscle only

D) Away from receptor only

Answer: B

Q15. Efferent means:

A) Towards CNS

B) Towards receptor

C) Away from CNS

D) Towards sensory organ

Answer: C

Q16. Which is an example of an effector?

A) Muscle

B) Sensory receptor

C) Brain

D) Spinal cord

Answer: A

Q17. Which part coordinates many reflex actions?

A) Spinal cord

B) Cerebrum only

C) PNS only

D) Kidney

Answer: A

Q18. Which system carries sensory information to CNS?

A) Sensory/afferent pathway

B) Motor/efferent pathway

C) Skeletal system

D) Digestive system

Answer: A

Q19. Which system carries motor commands to muscles?

A) Sensory pathway

B) Motor/efferent pathway

C) Receptor pathway

D) Digestive pathway

Answer: B

Q20. Brain and spinal cord together are called:

A) PNS

B) CNS

C) ANS

D) Somatic system

Answer: B

Q21. Which division includes nerves outside brain and spinal cord?

A) CNS

B) PNS

C) Brain stem

D) Cerebrum

Answer: B

Q22. Which is mainly associated with conscious control of skeletal muscles?

A) Somatic nervous system

B) Autonomic nervous system

C) Digestive system

D) Endocrine system

Answer: A

Q23. Which regulates many involuntary internal functions?

A) Somatic nervous system

B) Autonomic nervous system

C) Skeletal system

D) Sensory receptor

Answer: B

Q24. The first structure to detect a stimulus is generally:

A) Receptor

B) Motor neuron

C) Effector

D) Muscle

Answer: A

Q25. What is the correct sensory pathway?

A) CNS → receptor

B) Receptor → sensory neuron → CNS

C) Muscle → CNS → receptor

D) CNS → motor neuron → receptor

Answer: B

Q26. What is the correct motor pathway?

A) Receptor → CNS

B) CNS → motor neuron → effector

C) Effector → CNS

D) Muscle → receptor

Answer: B

Q27. Which statement about PNS is correct?

A) It only contains the brain.

B) It connects CNS with the rest of the body.

C) It is the same as spinal cord.

D) It contains only muscles.

Answer: B

Q28. Which statement about CNS is correct?

A) It consists only of nerves.

B) It consists of brain and spinal cord.

C) It contains only sensory receptors.

D) It contains only muscles.

Answer: B

Q29. During withdrawal reflex, the immediate motor response can be coordinated by:

A) Spinal cord

B) Kidney

C) Liver

D) Stomach

Answer: A

Q30. Which sequence is correct?

A) Receptor → Sensory → CNS → Motor → Effector

B) Effector → Sensory → CNS → Receptor

C) CNS → Receptor → Sensory → Effector

D) Motor → Receptor → CNS → Sensory

Answer: A

16. 2 Marks Questions – 2 अंक

2 Marks Q1. What is the Central Nervous System?

CNS consists of the brain and spinal cord. It acts as the main processing and coordination centre of the nervous system.

2 Marks Q2. What is the Peripheral Nervous System?

PNS consists mainly of nerves outside the brain and spinal cord and connects the CNS with the rest of the body.

2 Marks Q3. What is the function of sensory neurons?

Sensory neurons carry information from receptors towards the CNS.

2 Marks Q4. What is the function of motor neurons?

Motor neurons carry commands from the CNS to effectors such as muscles or glands.

2 Marks Q5. What are the two major components of CNS?

Brain and spinal cord.

17. 3 Marks Questions – 3 अंक

3 Marks Q6. Differentiate between CNS and PNS.

CNS consists of brain and spinal cord and performs processing and coordination. PNS consists mainly of nerves outside CNS and connects the CNS with the rest of the body.

3 Marks Q7. Explain afferent and efferent pathways.

Afferent pathways carry sensory information towards CNS. Efferent pathways carry motor commands away from CNS towards effectors.

3 Marks Q8. Write three functions of spinal cord.

1. Carries impulses between brain and body.
2. Provides pathways for sensory and motor information.
3. Coordinates many reflex actions.

3 Marks Q9. What is the role of PNS?

PNS connects the CNS with sensory receptors, muscles and glands and carries sensory information to CNS and motor commands from CNS to effectors.

3 Marks Q10. Define sensory neuron, motor neuron and effector.

Sensory neuron carries impulses to CNS. Motor neuron carries impulses from CNS to effector. Effector is a muscle or gland that produces a response.

18. 4 Marks Questions – 4 अंक

4 Marks Q11. Explain the organisation of the nervous system.

The nervous system is broadly divided into CNS and PNS. CNS consists of brain and spinal cord. PNS consists mainly of nerves outside CNS. Sensory pathways carry information towards CNS, while motor pathways carry commands from CNS to effectors.

4 Marks Q12. Explain the functions of CNS.

1. Receives sensory information.
2. Processes and interprets information.
3. Coordinates responses.
4. Controls and regulates many voluntary, involuntary and reflex activities.

4 Marks Q13. Explain the functions of PNS.

PNS connects CNS with the rest of the body. It carries sensory information from receptors to CNS and carries motor commands from CNS to muscles and glands.

4 Marks Q14. Differentiate between sensory and motor neurons.

Sensory Neuron	Motor Neuron
Carries impulses towards CNS.	Carries impulses away from CNS.
Receives information from receptors.	Activates effectors.
Afferent pathway.	Efferent pathway.
Example: skin receptor to CNS.	Example: CNS to arm muscle.

4 Marks Q15. Explain the role of spinal cord in the nervous system.

The spinal cord carries sensory and motor information between the brain and body and also acts as an important centre for coordinating many reflex actions.

19. 5 Marks Questions – 5 अंक

5 Marks Q16. Explain the Central Nervous System in detail.

CNS consists of brain and spinal cord. Brain is the main processing and control centre. It receives and interprets sensory information and coordinates responses. The spinal cord carries information between brain and body and coordinates many reflex actions.

5 Marks Q17. Explain the Peripheral Nervous System in detail.

PNS consists mainly of nerves outside the brain and spinal cord. It connects CNS with sensory receptors, muscles and glands. Sensory pathways carry information towards CNS, while motor pathways carry commands away from CNS.

5 Marks Q18. Explain the difference between CNS and PNS with five points.

1. CNS = brain + spinal cord; PNS = nerves outside CNS.
2. CNS is the main processing centre; PNS is mainly the communication network.
3. CNS interprets and integrates information; PNS carries information.
4. Spinal cord coordinates many reflexes; PNS carries signals involved in reflex pathways.
5. CNS is protected by skull/vertebral column; PNS nerves extend throughout the body.

5 Marks Q19. Explain sensory and motor pathways with an example.

Sensory pathways carry information from receptors to CNS. Motor pathways carry commands from CNS to effectors. For example, when touching a hot object, skin receptors detect heat, sensory neurons carry information to CNS, and motor neurons activate arm muscles to withdraw the hand.

5 Marks Q20. Explain the importance of CNS and PNS in coordination.

CNS processes information and coordinates responses. PNS establishes communication between CNS and the body. Together they allow the body to detect stimuli, process information and produce appropriate responses.

20. 6 Marks Questions – 6 अंक

6 Marks Q21. Explain the complete organisation of the human nervous system.

The nervous system is broadly divided into CNS and PNS.

CNS: Consists of brain and spinal cord. It is the main processing and coordination centre.

PNS: Consists mainly of nerves outside CNS and connects the CNS with the body.

Sensory/Afferent pathways: Carry information from receptors to CNS.

Motor/Efferent pathways: Carry commands from CNS to effectors.

This organisation enables rapid communication and coordination throughout the body.

6 Marks Q22. Compare Central Nervous System and Peripheral Nervous System.

Basis	CNS	PNS
Components	Brain and spinal cord	Mainly nerves outside CNS
Role	Processing and coordination	Communication with body
Sensory function	Processes sensory information	Carries sensory information
Motor function	Generates/coordinates motor responses	Carries motor commands to effectors
Protection	Skull and vertebral column protect major parts	Nerves extend throughout body
Example	Brain and spinal cord	Peripheral nerves

6 Marks Q23. Explain the pathway of information from receptor to effector.

1. A stimulus acts on a receptor.
2. Receptor detects the stimulus.
3. Sensory neuron carries information towards CNS.
4. CNS processes/integrates the information.
5. Motor neuron carries the command away from CNS.
6. Effector produces the response.

Pathway: Receptor → Sensory Neuron → CNS → Motor Neuron → Effector.

6 Marks Q24. Explain the role of CNS and PNS in a reflex action.

The receptor detects the stimulus. The sensory pathway of PNS carries the impulse towards CNS. The spinal cord, a part of CNS, coordinates the immediate reflex response. The motor pathway of PNS carries the command to the effector muscle. The muscle contracts and produces the response. Sensory information can also reach the brain.

6 Marks Q25. Explain sensory and motor divisions of the nervous system.

The sensory division carries information from receptors towards CNS and is also called the afferent pathway. The motor division carries commands away from CNS and is called the efferent pathway. Motor control includes pathways associated with skeletal muscles and pathways regulating many involuntary functions of internal organs and glands.

6 Marks Q26. Explain the importance of spinal cord in coordination.

The spinal cord is a major communication pathway between brain and body. It carries sensory information towards the brain and motor commands towards the body. It also contains neural circuits that coordinate many reflex actions, allowing rapid protective responses.

6 Marks Q27. What would happen if the sensory pathway were damaged?

If the sensory pathway is damaged, sensory information from the affected receptor may not reach the CNS normally. This can lead to reduced or absent sensation and may interfere with reflex responses that depend on that pathway.

6 Marks Q28. What would happen if the motor pathway were damaged?

If the motor pathway is damaged, commands from the CNS may not reach the appropriate effector normally. As a result, the corresponding muscle or gland may show reduced or absent response.

6 Marks Q29. Explain how CNS and PNS work together to coordinate the body.

PNS detects and carries sensory information from receptors to CNS. CNS processes this information and determines an appropriate response. PNS then carries motor commands from CNS to muscles or glands. Thus, CNS acts as the processing centre while PNS acts as a communication network between CNS and the rest of the body.

6 Marks Q30. Draw a labelled diagram showing the organisation of CNS and PNS and explain it.

Required labels:
Brain → Spinal Cord → Peripheral Nerves.

The diagram should clearly show that brain and spinal cord form CNS, while peripheral nerves form PNS and connect CNS with receptors and effectors throughout the body.

Flow: Receptor → Sensory Pathway → CNS → Motor Pathway → Effector.

21. HOTS / Competency Based Questions

HOTS 1: A person can feel a stimulus but cannot move the affected muscle properly. Which pathway may be affected?

Answer: The motor/efferent pathway may be affected because sensory information is reaching the CNS but the motor command is not reaching the effector normally.

HOTS 2: A person cannot properly feel a stimulus from a particular region and also shows a reduced reflex response. What type of pathway could be involved?

Answer: The sensory/afferent pathway may be affected because sensory information may not reach the CNS normally.

HOTS 3: Why is the PNS necessary even though the brain and spinal cord form the CNS?

Answer: PNS connects the CNS with receptors, muscles and glands throughout the body. Without it, information could not efficiently travel between the CNS and peripheral body regions.

22. CBSE Golden Points – परीक्षा के लिए महत्वपूर्ण

⭐ Point 1: CNS = Brain + Spinal Cord.

⭐ Point 2: PNS = Nerves outside the brain and spinal cord.

⭐ Point 3: CNS is the main processing and coordination centre.

⭐ Point 4: PNS connects CNS with the rest of the body.

⭐ Point 5: Sensory/Afferent = Towards CNS.

⭐ Point 6: Motor/Efferent = Away from CNS.

⭐ Point 7: Sensory neuron → Receptor to CNS.

⭐ Point 8: Motor neuron → CNS to Effector.

⭐ Point 9: Spinal cord coordinates many reflex actions.

⭐ Point 10: Brain and spinal cord together form the Central Nervous System.

23. Quick Revision Table

Term	Remember
CNS	Brain + Spinal Cord
PNS	Nerves outside CNS
Afferent	Towards CNS
Efferent	Away from CNS
Sensory Neuron	Receptor → CNS
Motor Neuron	CNS → Effector
Spinal Cord	Pathway + many reflex responses
Effector	Muscle or gland

24. Diagram Labelling Practice

For CBSE examination, practise these labels:

• Brain
• Spinal Cord
• Central Nervous System (CNS)
• Peripheral Nervous System (PNS)
• Sensory Neuron
• Motor Neuron
• Receptor
• Effector
• Afferent Pathway
• Efferent Pathway

25. Super-Fast Memory Trick

CNS = THINK + PROCESS + COORDINATE

PNS = CONNECT + CARRY INFORMATION

AFFERENT = ARRIVES at CNS

EFFERENT = EXITS from CNS

Sensory → CNS → Motor

Exam Tip: यदि प्रश्न में “brain + spinal cord” दिया हो तो उत्तर CNS होगा। यदि “nerves connecting CNS with body” दिया हो तो PNS होगा। और “towards CNS / away from CNS” के लिए Afferent / Efferent याद रखें।