Zusammenfassung der Ressource
Nerve Impulses
- Anatomy of a
neurone
- Dendrons
- Dendrites
- Axon
- Phospholipid bilayer
- Sodium-Potassium
pump
- Sodium ion channel
- Potassium ion channel
- Schwann cells
- Myelin sheath
- Nodes of ranvier
- Synapse
- Presynaptic neurone
- Smooth ER
- Mitochondrion
- Synaptic vesicle
- Acetylcholine
- Ca2+ channel
- Acetylcholine transferase
- Choline
- Ethanoic acid
- Synaptic cleft
- 20-30 nm wide
- acetylcholinesterase
- acetylcholine
- Cholinergic synapse
- Postsynaptic neurone
- Na+ channel
- Activated by acetylcholine
- Inhibition
- Cl- chanels
- Makes postsynaptic
membrane more -ve
- Propogation of a nerve impulse
- Resting potential,
membrane polarised
- Influx of Na+,
depolarisation occurs
- charge change causes
opening of Na+ voltage-gated
chanels
- Depolarisation continues, K+
channels open and neurone
behind repolarises
- Na+ removed by active
transport, neurone back at
resting potential
- Summation
- Spatial Summation
- several presynaptic neurones
- Temporal summation
- single presynaptic neurone firing frequently