Question

Transmission of nerve impulse is unidirectional due to

• A. insulation of nerve fibre by medullary sheath
• B. neurotransmitter released only at axon ending
• C. neurotransmitter released only at dendrite ends
• D. both a and b

Answer 1

The correct option is B neurotransmitter released only at axon ending

Unidirectional transmission of a nerve impulse through nerve fibre is due to the fact that the neurotransmitter released only at axon ending and dendrites are only the receptors for the neurotransmitter.
Myelin is a lipid-rich (fatty) substance that surrounds nerve cell axons to insulate them and increase the rate at which electrical impulses (called action potentials) are passed along the axon.