Lab 18B - Neurophysiology of Nerve Impulses

The ability to respond to stimuli and convert them into nerve impulses
the ability to transmit an impulse
Resting membrane potential
Difference in electrical charge across the plasma membrane. The membrane would be POLARIZED.
Sodium Potassium Pumps
How does the membrane maintain the difference in electrical charge established by diffusion of ions?
-70 mv
What is the resting membrane potential of a frog?
-40mv and -90mv
What is the resting membrane potential in a human?
Threshold Stimulus
The amt of stimulus needed to create an action potential. NA+ rushes into the cell increasing the number of positive ions inside the cell and changing the membrane polarity
The interior surface fo the membrane becomes less negative and the exterior surface becomes less positive
K+ moves out of the cell causing the membrane potential to move in a negative direction.
The membrane has become more negative than resting potential. Until the channels close.
Absolute Refractory Period
What period is it when the sodium ion channels are open, the membrane is totally insensitive to additional stimuli, regardless of the force of the stimulus?
Relative Refractory period
What period is it during repolarization, the membrane may be stimulated if a very strong stimulus is used?
Nerve impulse
Another name for the action potential in neurons.
Compound nerve action potential
The cumulation of action potential of all neurons in a nerve
deep pressure, cold temperature
Name a couple of physical factors that can inhibit a nerve impulse.
What toxin blocks synaptic transmission by preventing the flow of neural impulses from neuron to neuron?
Conduction Velocity
What is the name of the velocity of the action potential along a neural membrane?
larger the nerve the faster the conduction velocity, myelinated nerves are faster than unmyelinated nerves
What is the relationship between myelination and size and conduction velocity?