Cards (6)

  • NMJ - point where motor neurone meets a skeletal muscle fibre
  • NMJ
    • Always uses Ach
    • Postsynaptic membrane folded into many clefts that store acetylcholinesterase
  • NMJ
    • Always uses Ach
    • Postsynaptic membrane folded into many clefts that store acetylcholinesterase
    • Postsynaptic membrane has more receptors
    • Impulses are always excitatory
    • Endpoint for the AP
    • Connects motor neurone to muscle
  • Neurone synapse
    • Many different neurotransmitters used
    • Membrane smooth with acetylcholinesterase found in central cleft
    • Postsynaptic membrane has fewer receptors
    • Impulses can be excitatory or inhibitory
    • A new AP is generated in the next neurone
    • Connects two neurones
  • Describe how the release of Ach into a NMJ causes the cell membrane of a muscle fibre to depolarise (3)
    • Movement by diffusion
    • Binding to receptors on postsynaptic membrane
    • Causing sodium channels to open
  • When an AP arrives at the synaptic cleft it results in the secretion of Ach into the synaptic cleft. Explain how (3)
    • Depolarisation of presynaptic membrane
    • Ca2+ channels open
    • Vesicles fuse with presynaptic membrane