1. Unit 3 – Key Area 1 Divisions of the nervous system and parts of the brain

2. KA 1: Divisions of the nervous system and parts of the brain
(a) CNS
Central Nervous System
(f) Localisation of brain functions
The Nervous System
(b) PNS
Peripheral Nervous System
(e) Cerebral Cortex
(c) Medulla and Cerebellum
(d) Limbic System

3. The Nervous System The central nervous system (CNS)
Peripheral nervous system (PNS)
Brain
Spinal Cord
Autonomic Nervous system (ANS)
Somatic Nervous system (SNS)
Sympathetic
Parasympathetic

4. The Peripheral Nervous System
The Peripheral Nervous System (PNS) is made up of:
Somatic nervous system (SNS)
Autonomic nervous system (ANS)

5. Somatic Nervous System
The SNS controls:
Voluntary movement of skeletal muscles
It is also responsible for reflex actions like the withdrawal of a limb by conduction of impulses to smooth muscle.

6. Autonomic Nervous System
The ANS is involved in homeostasis and regulates the body’s internal environment.
Homeostasis is the maintenance of the body’s internal environment within tolerable limits, despite changes to body’s external environment.
This control is involuntary.
Diagram from text book

7. Nerves of the ANS
Parasympathetic
nerves
Sympathetic nerves
The nerves of the ANS can be split into two groups and they emerge from the spinal cord to reach effectors such as:
cardiac muscle,
smooth muscle,
glands.

8. The Nervous System The central nervous system (CNS)
Peripheral nervous system (PNS)
Brain
Spinal Cord
Autonomic Nervous system (ANS)
Somatic Nervous system (SNS)
Sympathetic
Parasympathetic

9. Autonomic Nervous System
Sympathetic
Parasympathetic
‘speeds up’
Takes over when the body is active or excited.
‘fight or flight’
Increased heart rate
Increased breathing rate
Perspiration
Redistribution of blood from digestive system to the muscles
‘slows down’
Takes over at times of rest and relaxation.
‘rest and digest’
Normal heart rate
Normal breathing rate
Redistribution of blood from muscles to digestive system
As they have the opposite effects, the sympathetic and parasympathetic systems are said to be antagonistic

10. The Nervous System
Use what you know about the structure of the nervous system to fill in this summary of its structure.

11. The Nervous System The central nervous system (CNS)
Peripheral nervous system (PNS)
Brain
Spinal Cord
Autonomic Nervous system (ANS)
Somatic Nervous system (SNS)
Sympathetic
Parasympathetic