Neurophysiology

A  potassium enters, repolarizing the cell to a negative value.

B  potassium exits, repolarizing the cell to a negative value.

C  potassium enters, repolarizing the cell to a positive value.

D  potassium exits, depolarizing the cell to an even more negative value.

E  potassium enters, depolarizing the cell to a positive value.

A  a hill where the high point is the farthest away from the threshold value.

B  a valley where the low point is the farthest away from the threshold value.

C  a hill where the high point approaches the threshold value.

D  a valley where the low point approaches the threshold value.

A  opening of chemically gated calcium channels and diffusion of calcium out of the synaptic knob to the interstitial fluid.

B  opening of chemically gated calcium channels and diffusion of calcium into the synaptic knob.

C  closure of voltage-gated calcium channels in the synaptic knob membrane.

D  opening of voltage-gated calcium channels and diffusion of calcium into the synaptic knob.

E  opening of voltage-gated calcium channels and diffusion of calcium out of the synaptic knob to the interstitial fluid.

A  IPSP.

B  EPSP.

A  FALSE

B  TRUE

A  TRUE

B  FALSE

A  suprathreshold hyperpolarization.

B  temporal summation.

C  several action potentials.

D  spatial summation.

A  D fibers, and they conduct impulses at 0.01 meter per second.

B  C fibers, and they conduct impulses at 100 meters per second.

C  A fibers, and they conduct impulses at 10 meters per second.

D  D fibers, and they conduct impulses at 0.1 meter per second.

E  C fibers, and they conduct impulses at 1 meter per second.

A  neurofibril nodes.

B  myelinated regions.

A  temporal summation.

B  presynaptic potentiation.

C  recruitment.

D  facilitation.

E  spatial summation.

A  lasts for several seconds after ion channels have opened, closed, and reset.

B  travels the length of the nerve fiber (is long-distance).

C  varies in size depending on the magnitude of the stimulus (larger voltage change for stronger stimulus).

D  is all or none (always the same intensity).

A  Relative refractory period

B  Absolute refractory period

A  one electrode inside the cell and another inside another cell.

B  two electrodes inside the neuron.

C  one microelectrode inside the neuron and another in the interstitial fluid.

D  one electrode inside the cell and another outside the body.

A  mechanically gated channels.

B  sodium-potassium pumps.

C  voltage-gated channels.

D  chemically gated channels.

A  degradation by an enzyme.

B  uptake by the postsynaptic cell.

C  being engulfed by a supporting glial cell.

D  reuptake by the presynaptic cell.

A  either the entry of an anion or the exit of a cation.

B  either the entry of a cation or the exit of an anion.

C  the entry of any ion.

D  the entrance of either sodium or potassium.

A  voltage-, axon

B  chemically, axon

C  chemically, dendrite

D  voltage-, dendrite

A  directly related to both voltage and resistance.

B  indirectly related to voltage and directly related to resistance.

C  inversely related to both voltage and resistance.

D  directly related to voltage and inversely related to resistance.

A  dendritic lassos.

B  endocytosis by the postsynaptic cell.

C  phagocytosis by a macrophage.

D  reuptake by the presynaptic cell.

A  their activated state to their resting state.

B  their resting state to their activated state.

C  their inactivated state to their resting state.

D  their resting state to their inactivated state.