What does peripheral nervous system PNS do
• sends messages to whole body from brain and relay neurones back to brain
Wt r the 2 sections in PNS
• somatic system= transmits + receives message via senses
• autonomic system= separated into 2 further groups transmits and receives messages from organs
- sympathetic- increases activity
- parasympathetic- helps conserve body activity
3 types of neurones
- sensory: peripheral nervous system carriers- long dendrites and short axons
- motor: signals from cns towards organs and muscles and glands connected to motor neurone
- relay- interneurones take on role of sensory motor neurones
What’s a synapse
• junction where 2 receptors meet consists of presynatpic cleft post synaptic membrane
Give stages of synaptic transmission 5stages
1• impulse arrives at end of presynaptic neurone
2• vesicles move towards+ fuse w presynaptic membrane releasing neurotransmitters into synaptic cledt
3• neyronstranitteds diffuse across synaptic cleft
4• neurotransmitters attach into receptors on post synaptic membrane
5• triggers impulse travels along post synaptic neurone
