The Divisions Of The Nervous System

Question 1

What are the divisions of the nervous system?

Answer 1

• Central nervous system -> the Brain and Spinal Cord
• Peripheral nervous system -> Somatic nervous system and Autonomic nervous system (containing the sympathetic and parasympathetic branch)

Question 2

Describe the brain

Answer 2

• involved in all psychological processes and its main job is to ensure life is maintained
• there are many parts of the brain, some are more primitive and involved with vital functioning like breathing and our heartbeat (e.g. brain stem)
• other areas are involved in high order thinking such as planning and problem solving (e.g. pre-frontal cortex)

Question 3

Describe the spinal cord

Answer 3

• Carries messages (using neurons) to and from the brain to the PNS
• in other words the spine relays information to and from he brain to the rest of the body
• this allows the brain to monitor bodily processes like breathing and digestion, and co-ordinate all bodily movements

Question 4

Outline what is meant by an arc reflex

Answer 4

Receptor in the skin detects a stimulus, neurotransmitters travel to the spinal cord which activates spinal motor neurons - this means there isn’t the delay of running the message through the brain

Question 5

How many pairs of cranial nerves are there?

How many pairs of spinal nerves are there?

Answer 5

• 12

- 31

Question 6

What is the peripheral nervous system?

Answer 6

• All nerves in the body outside the CNS are known as the PNS
• Main job is to relay nerve impulses from body -> brain -> body
• Cranial and spinal nerves allow CNS to be aware of what’s going on in the body
• this allows CNS to control our various response systems

Question 7

What is the Somatic nervous system

Answer 7

• regulates voluntary body movements
• part of the PNS connects brain to motor neurons (such as those found in the skeletal muscles)
• we are in control of this system and we use it when we want to make our muscles move
• two processes : motor and sensory

Question 8

What is the Autonomic nervous system?

Answer 8

• involuntary
• regulates the functions of our internal organs
• part of the PNS -> controls some of the muscles in our body
• 2 sections : sympathetic branch (switches on fight or flight) and parasympathetic branch (switches off fight or flight)

Question 9

What are the 4 differences between the SNS and ANS?

Answer 9

• ANS is involuntary whereas SNS is under conscious control
• SNS has both sensory and motor neurons, ANS only uses motor
• ANS controls internal organs/glands whereas SNS controls skeletal muscle and movement
• The control centre for the SNS is located in the motor and somatosensory cortex whereas the control centre for the ANS is located in the hypothalamus and pituitary gland