In a synapse, which neuron is the presynaptic cell?

In a synapse, which neuron is the presynaptic cell?

• A. Postsynaptic Neuron
• B. Neuron That Sends Message
• C. Neuron That Receives the Signal
• D. Glial Cell

Answer: (B)

The presynaptic cell is the neuron that sends the signal across the synapse. When an action potential arrives at the axon terminal of this neuron, calcium channels open, triggering the release of neurotransmitters into the synaptic cleft. These chemicals then bind to receptors on the postsynaptic neuron, conveying the message. The postsynaptic neuron is the one that receives the signal, while glial cells support and modulate activity rather than serving as the presynaptic transmitter source in the typical sense. So the neuron that sends the message is the presynaptic cell.

The presynaptic cell is the neuron that sends the signal across the synapse. When an action potential arrives at the axon terminal of this neuron, calcium channels open, triggering the release of neurotransmitters into the synaptic cleft. These chemicals then bind to receptors on the postsynaptic neuron, conveying the message. The postsynaptic neuron is the one that receives the signal, while glial cells support and modulate activity rather than serving as the presynaptic transmitter source in the typical sense. So the neuron that sends the message is the presynaptic cell.