1. ACTION POTENTIA
L PART 3
You will learn about:
Passing a Signal from a Neuron to a Receiving Cell
Course Outcome: CO1
2. what happens when the Action
Potential arrives at the end of the neuron?
• The signal must be passed to another cell.
• This occurs at a synapse.
• Relay point, between a neuron and a
receiving cell.
3. Synapse
Chemical- Chemical synapses are prevalent in most other organs, including
skeletal muscles, and in the central nervous system.
Electrical- electric current passes directly from one neuron to the next. In the
human body, electrical synapses are found in the heart and digestive tract,
where they help maintain steady, rhythmic muscle contractions.
4. Chemical
Synapse
Synaptic cleft – A narrow gap separating the
synaptic terminal of the sending neuron from
the receiving cell.
Action potential is converted to chemical
signal consisting of molecules of
neurotransmitter.
neurotransmitter is a chemical that carries
information from a nerve cell to another cell.
An action potential may then be generated in
the receiving cell.
6. Neurotransmitters
Chemical synapses can process extremely complex information. A neuron may receive input
from hundreds of other neurons via thousands of synaptic terminals . The inputs can be highly
varied because each sending neuron may secrete a different quantity or kind of
neurotransmitter. These factors account for the nervous system’s ability to process huge
amounts of complex stimuli and formulate appropriate responses
Some neurotransmitters are:
• Serotonin
• dopamine
• Endorphin
• Epinephrine
• Oxytocin
7. Action potential converted to chemical signal
Reuptake- Neurotransmitters are broken
down or taken back by the sending neuron
