system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Unidirectional flow of a nerve impulse is at:
assistant
The correct answer is  A i.e. SynapseSynapses generally permit conduction of impulses in one direction only, from presynaptic to post-synaptic neurons. Any impulse conducted antidromically up the axons dies out because, post synaptical pa of neurons lack chemical synaptic vesiclesQ that are needed for synaptic transmission. Therefore an impulse arriving at the post synaptic membrane cannot release synaptic mediator.Axons can conduct impulse in both direction.Dendrites are found on the axon's endings and so behave in the same way as the axons i.e. bi-directional.