Which of the following is NOT true of a synapse?

Options

A. Neurotransmitter affect postsynaptic neurons
B. Many neurons may be involved
C. A synaptic cleft separates the neurons of the synapse
D. Neurotransmitters are released from dendrites

Answer

To determine which statement is NOT true of a synapse, let's analyze each option step by step.

### Step 1: Analyze the Options

1. **Neurotransmitter effect post-synaptic neurons.**
- In a chemical synapse, neurotransmitters are indeed released from the pre-synaptic neuron and bind to receptors on the post-synaptic neuron. This statement is true.

2. **Many neurons may be involved.**
- A single neuron can connect with multiple other neurons through its dendrites and axon terminals. This means that many neurons can indeed be involved in synaptic connections. This statement is true.

3. **A synaptic cleft separates the neurons of the synapse.**
- The synaptic cleft is the small gap between the pre-synaptic and post-synaptic neurons. This statement is also true.

4. **Neurotransmitters are released from dendrites.**
- This statement is incorrect. Neurotransmitters are released from the axon terminal of the pre-synaptic neuron, not from dendrites. Dendrites receive signals but do not release neurotransmitters.

### Conclusion

The statement that is NOT true of a synapse is: **"Neurotransmitters are released from dendrites."**