Central Nervous System Flashcards
what order does the reflex arc follow
Stimulus, receptor, coordination, effector, response
What does the autonomic nervous system do?
Controls your body for you without you noticing, it is calming
What does the sympathetic division do?
It is arousing
Examples of parasympathetic nerves
Construct pupils
Stimulate saliva
Slow heart beat
Constrict airways
Etc
Sympathetic nerves examples
Dilate pupils
Inhibit salivation
increase heartbeat
Relax airways
Etc
What are the types of neurones
Sensory, motor, intermediate
What is the structure of the neuron
Cell body, dendrons, axon, myelin sheath, Schwann cells, nodes of ranvier
In a neuron what does the cell body do
Contains all the organelles including the nucleus and a large amount of rough ER to produce proteins and neurotransmitters
what does dendrons do in a neuron
extension of the cell body which subdivide into smaller branched fibres call dendrites that carry nerve impulses towards the cell body.
In a neuron what do axons do
The long single fibre that carries nerve impulses away from the cell body towards the axion terminal.
In neurons what do Schwann cells do
surround the axon providing protection and electrical insulation. They are wrapped in layers around the axon
In a neuron what does the myelin sheath do
forms a covering to the axon and is made up on the membranes of the Schwann cells . Membranes are made of myelin which is rich in lipids – neurons with this sheath are known and myelinated neurones – white matter
What do nodes of Ranvier do
constrictions between adjacent Schwann cells where there is no myelin sheath. They are 2-3um long and occur every 1-3mm in humans.
What is a nerve
A bundle of axons carrying information
In Parkinson’s disease what is missing in the brain
SN(substantial Nigra) (they are cells that produce dopamine)
