Explain the process of an action potential. Include synaptic transmission in your explanation
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This stuff is pretty hard to explain with just words. I recommend looking up an animation from McGraw-Hill, but I'll give it a shot.
Let's look at your standard neuron in the nervous system. It consists of dendrites, a soma, an axon, and synaptic knobs. Action potentials can be thought of as a way for cells to communicate. A neuron has a resting membrane potential of -70 mV (millivolts). This is due to the action of the Sodium/Potassium Pump and Potassium Leak Channels. When an action potential reaches a neuron (and it's intense enough), voltage-gated sodium channels open which cause an influx of positively charged sodium ions to come flying in, depolarizing the neuron from -70 to +35 mV. Once it reaches +35 mV, the voltage-gated sodium channels close and voltage-gated potassium channels open. This causes positively charged potassium ions to leave the neuron, repolarizing it. These gates close slowly, however, leading to hyperpolarization (-90 mV). But the neuron soon goes back to its resting membrane potential of -70 mV due to the Sodium/Potassium Pump and Potassium Leak Channels which have still been working the whole time.
This process continues down the axon of the neuron. When it reaches the end of it, it cause voltage-gated calcium channels to open, which trigger vessicles of a neurotransmitter (Acetylcholine is the most common) to be released from the synaptic knobs. This neurotransmitter will travel across the synapse and attempt to cause an action potential to the next neuron.
Let's look at your standard neuron in the nervous system. It consists of dendrites, a soma, an axon, and synaptic knobs. Action potentials can be thought of as a way for cells to communicate. A neuron has a resting membrane potential of -70 mV (millivolts). This is due to the action of the Sodium/Potassium Pump and Potassium Leak Channels. When an action potential reaches a neuron (and it's intense enough), voltage-gated sodium channels open which cause an influx of positively charged sodium ions to come flying in, depolarizing the neuron from -70 to +35 mV. Once it reaches +35 mV, the voltage-gated sodium channels close and voltage-gated potassium channels open. This causes positively charged potassium ions to leave the neuron, repolarizing it. These gates close slowly, however, leading to hyperpolarization (-90 mV). But the neuron soon goes back to its resting membrane potential of -70 mV due to the Sodium/Potassium Pump and Potassium Leak Channels which have still been working the whole time.
This process continues down the axon of the neuron. When it reaches the end of it, it cause voltage-gated calcium channels to open, which trigger vessicles of a neurotransmitter (Acetylcholine is the most common) to be released from the synaptic knobs. This neurotransmitter will travel across the synapse and attempt to cause an action potential to the next neuron.