6. BIOPSYCHOLOGY (THE DIVISIONS OF THE NERVOUS SYSTEM: CENTRAL AND PERIPHERAL (SOMATIC AND AUTONOMIC))

Question 1

What are the two main functions of the nervous system?

Answer 1

1. To collect, process, and respond to information in the environment.
2. To co-ordinate the working of different organs and cells in the body.

Question 2

What are the two main divisions of the nervous system?

Answer 2

1. The Central Nervous System (CNS)
2. The Peripheral Nervous System (PNS)

Question 3

What does the Central Nervous System (CNS) consist of, and what are its main functions?

Answer 3

• The CNS consists of the brain and spinal cord.
• Functions:
  1. Control of behaviour.
  2. Regulation of the body’s physiological processes.

Question 4

What role does the brain play in the nervous system?

Answer 4

• The brain is involved in psychological processes and ensures life is maintained.
• Some parts are concerned with vital functions (e.g., breathing), while others are involved in higher-order thinking like problem-solving and planning.

Question 5

What is the function of the spinal cord in the nervous system?

Answer 5

• The spinal cord transfers electrical impulses between the brain and the peripheral nervous system (PNS).
• It helps the brain monitor and regulate bodily processes, like digestion and breathing.
• It also contains circuits for simple reflexes (e.g., pulling your hand away from something hot).

Question 6

What is the role of the Peripheral Nervous System (PNS)?

Answer 6

• The PNS sends information to the CNS from the outside world and transmits messages from the CNS to muscles and glands in the body.
• It is divided into the Autonomic Nervous System (ANS) and the Somatic Nervous System (SNS).

Question 7

What does the Somatic Nervous System (SNS) do?

Answer 7

• The SNS transmits information from sense organs to the CNS and sends information from the CNS to muscles for movement.
• It consists of cranial nerves and spinal nerves, which carry both sensory neurons and relay neurons.

Question 8

What is the function of the Autonomic Nervous System (ANS)?

Answer 8

• The ANS is responsible for unconscious bodily functions such as breathing and digestion.
• It transmits impulses from the organs and has two divisions: the sympathetic nervous system and the parasympathetic nervous system.

Question 9

What is the function of the Sympathetic Nervous System (SNS)?

Answer 9

• The SNS prepares the body for action, increasing energy expenditure.
• It activates organs like the heart and lungs to work harder and signals the liver to release glucose for energy.

Question 10

What is the function of the Parasympathetic Nervous System (PNS)?

Answer 10

• The PNS helps the body to relax and conserve energy.
• It promotes digestion and slows down the heart and breathing rates.

Question 11

How do the Sympathetic and Parasympathetic Nervous Systems affect the body’s organs differently?

Answer 11

• They have opposite or antagonistic effects on most organs in the body.

Question 12

How does the Sympathetic Nervous System affect the eyes, lungs, saliva, heart, gut, immune system, and blood vessels?

Answer 12

1. Eyes: Dilates pupils to improve vision.
2. Lungs: Increases breathing rate to take in more oxygen.
3. Saliva: Decreases saliva production (dry mouth).
4. Heart: Increases heart rate to supply more oxygenated blood.
5. Gut: Slows digestion.
6. Immune System: Decreases immune response (less focus on repair and defence).
7. Blood Vessels: Constricts blood vessels to direct blood to essential muscles.

Question 13

How does the Parasympathetic Nervous System affect the eyes, lungs, saliva, heart, gut, immune system, and blood vessels?

Answer 13

1. Eyes: Constricts pupils.
2. Lungs: Decreases breathing rate.
3. Saliva: Increases saliva production.
4. Heart: Slows heart rate.
5. Gut: Increases digestion and promotes absorption of nutrients.
6. Immune System: Enhances immune response (favours repair and defence).
7. Blood Vessels: Dilates blood vessels to allow for greater blood flow.

Question 14

What types of neurons are present in the Somatic Nervous System (SNS)?

Answer 14

• The SNS contains sensory neurons and relay neurons, which help transmit signals from sense organs to the CNS and from the CNS to muscles for movement.

Question 15

What is the difference between the sympathetic and parasympathetic nervous systems in terms of energy?

Answer 15

• The sympathetic nervous system is responsible for the “fight or flight” response, increasing energy and arousal.
• The parasympathetic nervous system is responsible for “rest and digest,” conserving energy and promoting relaxation.