Please enable JavaScript.

Coggle requires JavaScript to display documents.

4b Types of synapses ( most common types) (Physiological classification,…

- - - - synaptic cleft wider (30nm)
        &
        
        filled with dense extracellular
        material
        
        Eg: Axodendritic synapse
  - - - synaptic cleft is narrow(20nm)
        &
        
        no such dense materials found here
        
        Eg: Axosomatic synapse
- - - - Most synaptic
        transmission are chemical
    - - An impulse reaches the
        excitatory synaptic bouton
        
        Results in
        release of a
        transmitter substance
        into the synaptic cleft
        
        Increased permeability of
        postsynaptic membrane to
        Na+ & K+
        
        results in
        Greater Na+ influx
        than K+ efflux
        due to greater
        electrochemical gradient
        for Na+
        
        The resultant current flow
        is in a direction
        that tends to depolarize the
        postsynaptic cell
        
        if threshold is reached- an action potential
        occurs in the postsynaptic cell
      - An impulse reaching the
        inhibitory synaptic bouton
        
        results in
        the release of a
        transmitter substance
        into the synaptic cleft
        
        Incr permeability of
        postsynaptic membrane to
        Cl- results in Cl- influx
        
        The resultant current flow is in a direction
        that tends to
        hyperpolarize the postsynaptic cell
        
        as a result greater depolarization
        of the postsynaptic cell
        is required to reach
        threshold