How is the nerve impulse transmitted across a synapse ? Explain.
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How does the nerve impulse travels across the synapse.
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Name two types of synapse. How does the nerve impulse cross the synapse with wide synaptic creft ?
There are two types of synapses - electrical synapses and chemical synapses.
Conduction and transmission of nerve impulse across a synapse : The theory of chemical transmission or synaptic transmission states that a chemical substance, acetylcholine, is liberated at the synapse and it diffuses through the synaptic transmission occurs in the following way :
(a) Release of a neurotransmitter substance at the tip of axon from the synaptic vesicles through presynaptic membrane.
(b) Diffusion of this chemical substance, acetylcholine cross the synaptic cleft.
© Combination of acetylcholine with a chemireceptor on the post synaptic membrane.
(d) Depolarization of the post synaptic membrane by neuro-transmitter substance initiate a fresh impulse or action potential passing through the neurons.
(e) Inactivation of acetylcholine by an enzyme acetylcholine esterase in the post synaptic membrane.
Acetylcholine Enzyme