Why do impulses in a neuron travel in one direction only?

Explanation

### Step-by-Step Solution:

1. **Understanding Neurons**: Neurons, or nerve cells, are specialized cells that transmit nerve impulses throughout the body. They communicate with each other at junctions called synapses.

2. **Structure of Synapse**: A synapse is the gap between two neurons. It consists of the presynaptic neuron (sending the impulse) and the postsynaptic neuron (receiving the impulse).

3. **Role of Neurotransmitters**: When an impulse reaches the end of a neuron, it triggers the release of neurotransmitters from the presynaptic neuron. These chemicals cross the synaptic gap and bind to receptors on the postsynaptic neuron.

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