Nervous system Flashcards
Briefly break down the structure of the nervous system
Nervous system = central nervous system + peripheral nervous system
Central Nervous System = Brain + Spinal Cord
Peripheral Nervous System = Autonomic + somatic nervous system
Autonomic Nervous System = Sympathetic + parasympathetic nervous system
Define the CNS
The central nervous system consists of the brain and spinal cord. It receives information via the bodies senses and controls its responses.
Define the Brain
The part of the CNS responsible for the coordination of sensation, intellectual and nervous activity.
Define the Spinal Cord
A bundle of nerve fibres enclosed within the spinal column that connect almost all parts of the body with the brain.
Define the Peripheral nervous system
Part of the nervous system outside the brain and spinal cord
Define the Somatic nervous system
The part of the PNS responsible for carrying sensory and motor information to and from the central nervous sytem.
Define the Autonomic nervous sytem
Governs the bodies involuntary functions i.e stress and heartbeat and is self-regulating i.e autonomous. Is further broken down into the sympathetic and parasympathetic branches.
What are the 2 functions of the CNS?
1) Regulation of the bodies physiological processes
2) Control of behaviour
How does the spinal cord perform quick reflexes?
The spinal cord is also made of a circuit of spinal nerves that allow quick reflexes to be made without the involvement of the brain to save time in cases of emergency.
What happens if the spinal cord is damaged?
If the spinal cord is damaged, the areas supplied below the damaged site will be cut off from the brain and also stop functioning.
What are the 4 main divisions of the brain?
1) Cerebrum
2) Cerebellum
3) Diencephalon
4) Brain Stem
Describe the cerebrum
Largest part of brain, further split into 4 lobes that all have different functions:
Frontal lobe - involved with speech, learning and thought
Temporal lobe - involved with hearing, and memory
Occupital lobe - involved with processing of visual info
Parietal lobe - involved with processing sensory info like touch, pain and temperature
Cerebrum is also broken into 2 halves called a hemisphere, the left and right hemispheres each specialised in different behaviours and communicate with one another via corpus callosum.
Describe cerebellum
Sits beneath back of cerebrum. Involved in controlling motor skills and balance, coordinating muscles to allow precise movement
Abnormalities here result in epilepsy and speech and motor problems.
Describe the diencephalon
Lies beneath cerebrum and on top of brain stem. Made up of thalamus and hypothalamus. Thalamus - acts as relay station for nerve impulses coming from senses, coordinating them to appropriate areas of brain to be processed. Hypothalamus - has a no. if vital functions like regulation of body temp, hunger and thirst. Also acts as link between the endocrine and nervous system by controlling the release of hormones from the pituitary gland.
Describe the brain stem
Regulates autonomic functions vital for life i.e breathing, heartbeat, and swallowing. Motor and sensory neurons also travel through here allowing nerve impulses to be passed between brain and spinal cord.
