presynaptic terminal

biology

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June 17, 2026

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The presynaptic terminal is the end of a neuron where neurotransmitters are released to transmit signals to another neuron, gland, or muscle cell. This process occurs at a synapse, a junction between cells. When an electrical impulse, or action potential, reaches the presynaptic terminal, it triggers the release of neurotransmitters stored in synaptic vesicles. These chemicals then cross the synaptic cleft and bind to receptors on the postsynaptic cell, either exciting or inhibiting it. This chemical transmission is crucial for the complex communication within the nervous system.12

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nervous system
Axon
Presynaptic terminals, when seen by light microscope, look like small knobs and contain many organelles. The most numerous of these are synaptic vesicles, which, filled with neurotransmitters, are often clumped in areas of the terminal membrane that appear to be thickened. The thickened areas are…
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Presynaptic terminals, when seen by light microscope, look like small knobs and contain many organelles. The most numerous of these are synaptic vesicles, which, filled with neurotransmitters, are often clumped in areas of the terminal membrane that appear to be thickened. The thickened areas are…
Read More

neurotransmitter
Neurotransmitter signaling
…end, also known as the presynaptic terminal. The presynaptic terminal is separated from the neuron or muscle or gland cell onto which it impinges by a gap called the synaptic cleft. The synaptic cleft, presynaptic terminal, and receiving dendrite of the next cell together form a junction known as the…
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…end, also known as the presynaptic terminal. The presynaptic terminal is separated from the neuron or muscle or gland cell onto which it impinges by a gap called the synaptic cleft. The synaptic cleft, presynaptic terminal, and receiving dendrite of the next cell together form a junction known as the…
Read More