Lab #6

The membrane potential is becoming more positive than the resting membrane potential

The membrane potential is moving from a more positive value toward resting membrane potential

The membrane potential is more negative than the resting membrane potential

Action potentials are due to which type of ion channels?

Where in the neuron is an action potential initially generated?

Which type of channel has an inactivation phase?

What is true about the opening of voltage-gated Na+ and K+ channels

What must happen before an action potential is generated?

What is meant when we say the action potential is an "all or none" event?

During the action potential, when does sodium permeability initially decrease?

The rapid decrease in sodium permeability and simultaneous increase in potassium permeability is responsible for

What is the approximate amplitude of an action potential?

What is true about the resting membrane potential (RMP)?

During the action potential of a neuron, which ion is primarily crossing the membrane during the depolarization phase, and in which direction is the ion moving?

What is happening to voltage gated channels at the peak of an action potential?

The repolarization phase of the action potential, where voltage becomes more negative after the +30mV peak is caused primarily by

During an action potential, hyperpolarization beyond the RMP is due to

During the hyperpolarization phase of the action potential what happens to voltage-gated ion channels

What is the direction of the ions when their voltage-gated channels open?

How is an action potential propagated along an axon?

Why does the action potential only move away from the cell body?

The velocity of the action potential is fastest in which of the following axons

The diffusion of what ion, across the neuronal membrane is responsible for the local currents that depolarize regions of the axon to the threshold?

An action potential in one segment of axon causes adjacent sections of axon membrane to reach threshold through what mechanisms?

During AP propagation in an unmyelinated axon, why doesn't the action potential suddenly "double back" and start propagating in the opposite direction

In a myelinated axon, how do the nodes of Ranvier differ from other segments of the same axon?

Where are action potentials regenerated as they propagate along a myelinated axon?

The node-to node "jumping regeneration of an action potential along a myelinated axon is called

If a myelinated neuron was affected by demyelination, how would this affect action potentials in that neuron

What is the significance of the refractory period

During the absolute refractory period

Relative refractory period

What is an example of a presynaptic cell?

Which of the following has a role in the postsynaptic cell during synaptic activity?

What is the role of calcium in synaptic activity?

What is the role of neurotransmitter at a chemical synapse?

Neurotransmitter is released from presynaptic neurons through what mechanism?

What type of channel on the postsynaptic membrane binds neurotransmitters?

Excitatory graded potentials fire an action potential from the

Mechanisms that terminate neurotransmitter activity

Graded (synaptic) potentials occur at