Närviterminaliks

Närviterminaliks, also known as a synaptic terminal or axon terminal, refers to the specialized structure at the end of a neuron's axon. This is where communication between neurons or between a neuron and an effector cell (like a muscle or gland cell) occurs. When an electrical impulse, called an action potential, reaches the närviterminaliks, it triggers the release of chemical messengers known as neurotransmitters.

These neurotransmitters are stored in small sacs called synaptic vesicles within the närviterminaliks. Upon arrival of the action potential, the vesicles fuse with the presynaptic membrane and release their contents into the synaptic cleft, the tiny gap between the two cells. The neurotransmitters then diffuse across the cleft and bind to specific receptors on the postsynaptic membrane of the next neuron or effector cell, thereby transmitting the signal.

The structure of the närviterminaliks is highly adapted for this function. It contains numerous mitochondria to provide the energy needed for neurotransmitter synthesis, storage, and release. It also possesses specialized protein machinery that facilitates vesicle trafficking and fusion. The precise shape and composition of the närviterminaliks can vary depending on the type of neuron and the specific neurotransmitters it releases, influencing the type and strength of the signal transmitted.