Neuron- So neurons are specialized to transmit/send information throughout your body. These nerve cells are just like any other cell, they have a nucleus. If you look at the picture above you will see the axons which branch our with long tails. They are connected to the axon terminal.
Ion Channels- They are made up of membrane proteins. Ion Channels allow some ions to pass through and prevents some others to pass, they are very selective. The ions diffuse and follow their electrochemical gradients as gate ions channels open. This tends to create electrical currents and voltage changes across the membrane.
Membrane Protein Pump- This is when the potassium has to come out to equalize the charges when the sodium pumps in.
Synaptic Potential- A synaptic potential occurs when neurons connect. It comes in two forms which are excitatory and inhibitory. So the sodium receptors detect the synapse and sodium is released into the membrane. The inside starts to become less negative while the outside will do the opposite and become less positive.
Resting Potential- When a neuron is not sending a signal it is at rest,
the inside of the neuron is negative relative to the outside. The resting membrane potential of a neuron is about -70 mV. So at rest there are more sodium ions outside the neuron and more potassium ions inside that neuron.
Action Potential- An action potential occurs when a neuron sends information down an axon away form a cell body. First a stimulus causes sodium channels to open, sodium ions then rush into the neuron. Sodium has a positive charge, the neuron becomes more positive, it then takes longer for the potassium channels to open. Potassium rushes out of the cell when they open, at this time sodium channels start to close and this action causes the action potential to go toward -70mV and it then goes past -70mV because the potassium channels stay open too long. Eventually ions concentration goes back to resting levels and the cell returns to -70mV
No comments:
Post a Comment