PNB 2264 Cumulative Exam Questions
Well Answered Graded A+.
A neuron that carries temperature information from the surface of the skin to the spinal cord
would be classified as: - Answer An afferent neuron
Events that happen in between opening the voltage gated sodium channel and crossbridge
formation refer to... - Answer Excitation contraction coupling
What does the I-band refer to? - Answer Actin (thin)
What does the A-band refer to? - Answer Overlap of actin and myosin
What does the H-zone refer to? - Answer Myosin
What are the filaments of myosin attached to on the ends? - Answer Z-discs
What happens to the size of the I-band during sarcomere contraction? - Answer It decreases
What happens to graded potentials over time and distance? - Answer They decrease
Where do graded potentials usually originate? - Answer The dendrites
Are graded potentials hyperpolarizing or depolarizing? - Answer Both
According to the G-H-K (parallel conductance) equation, if the permeability to sodium decreases
while the permeability to potassium and chloride remains the same what will happen to the
resting membrane potential? - Answer It will hyperpolarize
What does a motor unit consist of? - Answer A single motor neuron and all the muscle fibers
it innervates
Ion X is negatively charged. Its concentration outside the cell is 200mM, and its concentration
inside the cell is 50mM. The cell is permeable to ion X. The equilibrium potential for this ion
would be (negative/positive/zero) - Answer Negative
, What are the glial cells of the CNS? - Answer Astrocytes, ependymal, microglia,
oligodendrocytes
What are the glial cells of the PNS? - Answer Satellite cells, Schwann cells
What moves both sodium and potassium ions against their concentration gradients (from low
concentration to high concentration)? - Answer The sodium potassium pump
__________________ is muscle protein made up of monomers (globular) proteins that
polymerize to form chains (filaments) when ___________________ is present - Answer
Actin; ATP
What is calcium's role in muscle contraction? - Answer It binds troponin, opening up binding
sites on actin
What does the length-tension relationship state? - Answer The tension that can be generated
in a muscle fiber depends on the amount of overlap between thick and thin filaments
Which division of the nervous system includes the spinal cord and brain? - Answer The
central nervous system?
During muscle contraction, calcium enters the cytosol through the ___________. During
relaxation, calcium is removed from the cytoplasm by ____________. - Answer Ryanodine
receptor, SERCA
A neuron that has multiple dendrites and a single axon, all coming off of the soma, would be
classified as: - Answer A multipolar neuron
A neuron that has multiple dendrites and a single axon, all coming off of the soma, would be
classified as - Answer Gray matter
The concentration of sodium ions inside the cell is 10mM, and the extracellular concentration is
100mM. The equilibrium potential for sodium under these conditions is +58mV. If the
extracellular concentration of sodium was changed to 500mM, equilibrium potential: - Answer
Would be more positive
When is a positive feedback loop triggered in the action potential? - Answer During
depolarization
Well Answered Graded A+.
A neuron that carries temperature information from the surface of the skin to the spinal cord
would be classified as: - Answer An afferent neuron
Events that happen in between opening the voltage gated sodium channel and crossbridge
formation refer to... - Answer Excitation contraction coupling
What does the I-band refer to? - Answer Actin (thin)
What does the A-band refer to? - Answer Overlap of actin and myosin
What does the H-zone refer to? - Answer Myosin
What are the filaments of myosin attached to on the ends? - Answer Z-discs
What happens to the size of the I-band during sarcomere contraction? - Answer It decreases
What happens to graded potentials over time and distance? - Answer They decrease
Where do graded potentials usually originate? - Answer The dendrites
Are graded potentials hyperpolarizing or depolarizing? - Answer Both
According to the G-H-K (parallel conductance) equation, if the permeability to sodium decreases
while the permeability to potassium and chloride remains the same what will happen to the
resting membrane potential? - Answer It will hyperpolarize
What does a motor unit consist of? - Answer A single motor neuron and all the muscle fibers
it innervates
Ion X is negatively charged. Its concentration outside the cell is 200mM, and its concentration
inside the cell is 50mM. The cell is permeable to ion X. The equilibrium potential for this ion
would be (negative/positive/zero) - Answer Negative
, What are the glial cells of the CNS? - Answer Astrocytes, ependymal, microglia,
oligodendrocytes
What are the glial cells of the PNS? - Answer Satellite cells, Schwann cells
What moves both sodium and potassium ions against their concentration gradients (from low
concentration to high concentration)? - Answer The sodium potassium pump
__________________ is muscle protein made up of monomers (globular) proteins that
polymerize to form chains (filaments) when ___________________ is present - Answer
Actin; ATP
What is calcium's role in muscle contraction? - Answer It binds troponin, opening up binding
sites on actin
What does the length-tension relationship state? - Answer The tension that can be generated
in a muscle fiber depends on the amount of overlap between thick and thin filaments
Which division of the nervous system includes the spinal cord and brain? - Answer The
central nervous system?
During muscle contraction, calcium enters the cytosol through the ___________. During
relaxation, calcium is removed from the cytoplasm by ____________. - Answer Ryanodine
receptor, SERCA
A neuron that has multiple dendrites and a single axon, all coming off of the soma, would be
classified as: - Answer A multipolar neuron
A neuron that has multiple dendrites and a single axon, all coming off of the soma, would be
classified as - Answer Gray matter
The concentration of sodium ions inside the cell is 10mM, and the extracellular concentration is
100mM. The equilibrium potential for sodium under these conditions is +58mV. If the
extracellular concentration of sodium was changed to 500mM, equilibrium potential: - Answer
Would be more positive
When is a positive feedback loop triggered in the action potential? - Answer During
depolarization
