Neurotransmitter released by

Options

A. Axon terminal
B. Dendrite
C. Cell body
D. Myelin sheath

Answer

### Step-by-Step Solution:

1. **Understanding Neurotransmitters**: Neurotransmitters are chemical messengers that transmit signals across a chemical synapse from one neuron to another.

2. **Identifying the Source of Release**: The question asks where neurotransmitters are released from. The options provided are axon terminal, dendrite, cell body, and myelin sheath.

3. **Axon Terminal Function**: The axon terminal is the part of the neuron that is responsible for the release of neurotransmitters. When an electrical signal (action potential) reaches the axon terminal, it triggers the release of neurotransmitters into the synaptic cleft.

4. **Presynaptic Neuron**: The neuron that releases the neurotransmitter is referred to as the presynaptic neuron. The neurotransmitters then travel across the synaptic cleft to bind with receptors on the postsynaptic neuron, which is typically located on the dendrites.

5. **Neurotransmission Process**: This entire process of neurotransmitter release and binding to receptors is known as neurotransmission. It is crucial for communication between neurons.

6. **Conclusion**: Based on the above understanding, the correct answer to the question "Neurotransmitter released by" is the axon terminal.

### Final Answer:
**Neurotransmitter is released by the axon terminal.**

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