Axon Terminal

The axon terminal, also known as a synaptic knob, is the endpoint of a neuron where neurotransmitters are released to communicate with other neurons or target cells. It plays a crucial role in the transmission of electrical signals between neurons in the nervous system.

Anatomy of Axon Terminal

• Synaptic vesicles: Small sacs within the axon terminal that store neurotransmitters.
• Neurotransmitters: Chemical messengers that transmit signals across the synapse to a target cell.
• Synaptic cleft: The small gap between the axon terminal of one neuron and the dendrite of another neuron.
• Presynaptic membrane: The membrane of the axon terminal that faces the synaptic cleft.
• Postsynaptic membrane: The membrane of the neighboring neuron's dendrite that faces the synaptic cleft.

Function of Axon Terminal

When an action potential reaches the axon terminal, it triggers the release of neurotransmitters from the synaptic vesicles into the synaptic cleft. These neurotransmitters then bind to receptor sites on the postsynaptic membrane, leading to the generation of a new electrical signal in the next neuron, and thus transmitting the signal through the nervous system.

Study Guide

1. Describe the structure of the axon terminal and its components.
2. Explain the role of neurotransmitters in the function of the axon terminal.
3. Discuss the process of signal transmission at the synapse involving the axon terminal.
4. Compare and contrast the presynaptic and postsynaptic membranes in the context of the axon terminal.
5. Illustrate the communication between neurons using the axon terminal in a labeled diagram.

Understanding the anatomy and function of the axon terminal is essential for comprehending how signals are transmitted and processed in the nervous system.