Final answer:
The end of the axon where it makes contact with a target cell is known as the axon terminal or synaptic end bulb, which connects to another cell via a synapse.
Step-by-step explanation:
The termination point of a neuron's axon, where it establishes contact with a target cell, is referred to as the axon terminal or synaptic end bulb. This critical anatomical feature marks the endpoint of the axon and plays a pivotal role in transmitting nerve impulses to neighboring cells.
At the axon terminal, communication between neurons or between neurons and target cells occurs through specialized structures known as synapses. Synapses are functional junctions that enable the transfer of information from one neuron to another or from a neuron to an effector cell, such as a muscle or gland cell.
The process begins with the arrival of an action potential at the axon terminal. In response to this electrical signal, synaptic vesicles containing neurotransmitters are mobilized to the axon terminal's membrane. Neurotransmitters are chemical messengers that facilitate the transmission of signals across synapses.
Upon reaching the axon terminal membrane, the synaptic vesicles release neurotransmitters into the synaptic cleft—a small gap between the axon terminal and the adjacent cell, often a dendrite of another neuron. Neurotransmitters traverse this synaptic cleft and bind to specific receptors on the postsynaptic membrane of the receiving cell.
The binding of neurotransmitters to receptors initiates a series of events, ultimately leading to the generation of an action potential in the postsynaptic cell. This electrochemical signaling cascade ensures the transmission of nerve impulses from one neuron to the next or from a neuron to an effector cell, facilitating communication within the nervous system and coordinating various physiological responses. The intricate dynamics of synapses and neurotransmission are fundamental to the functioning of neural circuits and the overall integration of nervous system activities.