Get Answers to all your Questions

header-bg qa

Q6.    Give a brief account of:

         (a) Mechanism of synaptic transmission

Answers (1)

The mechanism of synaptic transmission at the electrical synapse:

  • In this case, the pre-synaptic and post-synaptic membranes are in proximity.
  • Impulse in the form of electric current directly flows from the pre-synaptic neuron to the post-synaptic neuron.
  • Transmission is faster than the chemical synapse.

The mechanism of synaptic transmission at the chemical synapse:

  • the pre-synaptic and post-synaptic neurons are separated by the synaptic cleft.
  • When an impulse arrives at the axon terminal, the calcium ions present in the synaptic cleft enter the synaptic knobs present at the axon terminals of the pre-synaptic neuron.
  • The synaptic vesicles present in the synaptic knobs present in the pre-synaptic neuron move towards the plasma membrane and fuse with it.
  • The vesicles release the neurotransmitter acetylcholine in the synaptic cleft. (Empty synaptic vesicles return to the cytoplasm of the pre-synaptic neuron where they are refilled.)
  • The molecules of the acetylcholine bind to the protein receptors present on the plasma membrane of the post-synaptic neurons.
  • This binding opens the channels, and sodium ions enter the post-synaptic neuron, while potassium ions leave the post-synaptic membrane.
  • This generates an action potential in the membrane of the post-synaptic neuron, and hence, the impulse is transmitted to the post-synaptic neuron.
Posted by

Priyanka Kumari

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support