Unit 9- nervous system Flashcards
what does the autonomic nervous system split into?
- the sympathetic system (fight and flight), noradrenaline
- the parasympathetic system (rest and digest) acetylcholine
describe the branches of the human nervous system:
human nervous system - peripheral and central nervous system peripheral splits into: - voluntary and autonomic nervous system Autonomic splits into: - sympathetic and parasympathetic system
Describe the structure of a sensory neurone
- long nerve fibre (mostly dendron)
- cell body more central (not at the end of the nerve
Describe the structure of a motor neurone
- long nerve fibre (axon)
- lots of dendrites on the cell body
- cell body is at the beginning of the nerve
Function of the medulla oblongata
- low level autonomic functions like breathing and heart rate
Function of cerebellum
- controls complex muscular coordination like walking or running
- also controls balance
Function of the hypothalamus:
- homeostasis regulation
- temperature regulation and osmoregulation
- controls the release of hormones from pituitary gland
Function of the cerebrum
Controls higher functions
- responsible for conscious thoughts
- movement are also initiated by cerebrum
Describe the reflex arc
- sensory nerve fibre enters via the dorsal root
- sensORy cell body lies in the dORsal root ganglion
- relay neurones carry impulses to motor neurones and also can connect to brain
- motor nerve fibres exit via the ventral root and stimulate effector cells
What type of nerves are in the dorsal root? And ventral root?
Dorsal- sensory neurone
Ventral- motor neurone
What is special about the cells in the grey matter of CNS?
Unmyelinated
What 2 regions make up the spinal cord?
- grey matter (unmyelinated interneurones)
- outer white matter made of sensory and motor neurones
What is the purpose of the ventral root ganglion
- it’s a swelling in the dorsal root containing all the sensory neurone cell bodies
Where is the cell body of a motor neurone found?
- in the grey matter
Definition of a reflex
A specific response to a specific stimulus which protects the body from damage