Problem 3 1.4
Inside the neuron
Action potential
Information is transferred via electrical impulses within neurons (action potential)
Information is transferred via neurotransmitters (chemical) between neurons
(synaptic transmission)
Electrical impulse- the movement of ions (small particles that have an electrical
charge) across the cell membrane of the axon of a neuron cause a potential
difference
The resting potential can be affected by electrical events. If the potential rises and a
certain potential (threshold) is reached, then the sodium ion channels in the cell
membrane will open and let sodium ions enter the neuron. The neuron is now
depolarised
At the peak of the sodium ion inflow, the sodium channels close, while the
potassium channels open. The potassium goes out of the neuron and the neuron
becomes repolarized and later hyperpolarised
All or nothing response- the strength of the action potential is always the same, it is
not influenced by the intensity of the stimulation. The voltage has to reach the
threshold of -55mv
Rate law- when a neuron is stimulated strongly, the frequency of the action potential
rises
The action potential depolarizes the areas that are close by
Saltatory conduction- the action potential at the node of Ranvier triggers the flow of
current to the next node, where the membrane regenerates the action potential.
Can only happen if the axon is myelinated
Refractory period:
Inside the neuron
Action potential
Information is transferred via electrical impulses within neurons (action potential)
Information is transferred via neurotransmitters (chemical) between neurons
(synaptic transmission)
Electrical impulse- the movement of ions (small particles that have an electrical
charge) across the cell membrane of the axon of a neuron cause a potential
difference
The resting potential can be affected by electrical events. If the potential rises and a
certain potential (threshold) is reached, then the sodium ion channels in the cell
membrane will open and let sodium ions enter the neuron. The neuron is now
depolarised
At the peak of the sodium ion inflow, the sodium channels close, while the
potassium channels open. The potassium goes out of the neuron and the neuron
becomes repolarized and later hyperpolarised
All or nothing response- the strength of the action potential is always the same, it is
not influenced by the intensity of the stimulation. The voltage has to reach the
threshold of -55mv
Rate law- when a neuron is stimulated strongly, the frequency of the action potential
rises
The action potential depolarizes the areas that are close by
Saltatory conduction- the action potential at the node of Ranvier triggers the flow of
current to the next node, where the membrane regenerates the action potential.
Can only happen if the axon is myelinated
Refractory period:
