Chapter 3.2

Myelin

________ increases the magnitude of the energy in the action potential and it increases the speed as well.

+40

The voltage-gated Na+ channel closes when the intracellular space reaches _______mV.

Saltatory conduction

________: the action potential travels inside the axon and jumps from node to node.

Neurons

________ calculate the overall postsynaptic input and indicate an action potential if depolarization exceeds the threshold and reaches its axon hillock.

Low

Sodium is drawn into the intracellular space due to the _____ concentration of it, as well as the overall negative charge inside.

threshold

Once the ________ is reached, an action potential occurs and the membrane potential reverses and the inside of the cell becomes positive.

+40

Voltage- gated K+ channels are the unique channels which open when the membrane potential is ________mV.

-40

Voltage- gated potassium channel closes when the intracellular space reaches ________mV.

Temporal summation

________ is the summoning of potentials that arrive at the axon hillock at different times.

Relative refractory phase

________: only strong stimulation can produce an action potential.

All-or-none property

_________________ of action potentials: the neuron fires at full amplitude or not at all- does not reflect increase stimulus strength.

Refractory period

________: only some stimuli can produce an action potential.

Spatial summation

________ is the summing of potentials that come from different parts of the cell.

Extracellular space

the sodium has left and there is a low concentration of sodium and potassium, leaving the extracellular space 40 mV more negatively charged in the intracellular space

Intracellular space

lots of sodium raises the electro static pressure of the intracellular space, saturated with sodium and potassium

Absolute refractory phase

no action potentials are produced