CBNS 120 MIDTERM 1 EXAM QUESTIONS AND ANSWERS
Cajal used the [_________] stain to prove the [___________] Doctrine. - CORRECT ANSWER✅✅golgi;
neuron
Conductance is the reciprocal of: - CORRECT ANSWER✅✅resistance
Hyperpolarization occurs when the membrane potential becomes more [_____________], while
depolarization causes the membrane potential to become more [_______________]. - CORRECT
ANSWER✅✅negative; positive
Permeability indicates the presence of ______, while conductance requires _______ and ______. -
CORRECT ANSWER✅✅open channels; ions; permeability
Permeability is the ability of the membrane to conduct _________ . - CORRECT ANSWER✅✅ions
Categories of ion channels include ________, _________, and _________. - CORRECT
ANSWER✅✅stretch-activated; voltage-activated; ligand-activated
Conductance can be distinguished from permeability by the requirement for ___________. - CORRECT
ANSWER✅✅charge
The membrane potential at which the diffusional force created by an ion gradient is equal and opposite
to the electrical force is called the [________________]. - CORRECT ANSWER✅✅equilibrium potential
The difference between the membrane potential (Vm) and the equilibrium potential (Ex) for any given
ion is called [_____________]. - CORRECT ANSWER✅✅driving force
When current flow across the membrane in one direction exceeds current flow in the opposite
direction, it is called ___________. - CORRECT ANSWER✅✅rectification
Ion channels flux (transfer) ions across the membrane at rates of
, a.) 10^7-10^8 ions/sec
b.) 10^3-10^5 ions/sec
c.) 10^2-10^3 ions/sec
d.) 10^9-10^10 ions/sec - CORRECT ANSWER✅✅10^7-10^8 ions/sec
Driving Force is:
a.) equals the difference between the equilibrium potential (Ex) and the membrane potential (Vm).
b.) zero when the Vm = Ex
c.) is required for current to flow across the membrane
d.) All of the above - CORRECT ANSWER✅✅d.) all of the above
Ion channel activity is:
a.) Random
b.) Stochastic
c.) Probablistic
d.) All of the above - CORRECT ANSWER✅✅d.) all of the above
In voltage-gated channels, the S4 transmembrane segment functions as a _______ and the region
between S5 and S6 functions as the ________. - CORRECT ANSWER✅✅voltage sensor; pore
Regions of channel proteins that cross the membrane from one side (extracellular) to the other
(cytoplasmic) are called:
A.) membrane-spanning
B.) transmembrane segments
C.) extracellular loops
Cajal used the [_________] stain to prove the [___________] Doctrine. - CORRECT ANSWER✅✅golgi;
neuron
Conductance is the reciprocal of: - CORRECT ANSWER✅✅resistance
Hyperpolarization occurs when the membrane potential becomes more [_____________], while
depolarization causes the membrane potential to become more [_______________]. - CORRECT
ANSWER✅✅negative; positive
Permeability indicates the presence of ______, while conductance requires _______ and ______. -
CORRECT ANSWER✅✅open channels; ions; permeability
Permeability is the ability of the membrane to conduct _________ . - CORRECT ANSWER✅✅ions
Categories of ion channels include ________, _________, and _________. - CORRECT
ANSWER✅✅stretch-activated; voltage-activated; ligand-activated
Conductance can be distinguished from permeability by the requirement for ___________. - CORRECT
ANSWER✅✅charge
The membrane potential at which the diffusional force created by an ion gradient is equal and opposite
to the electrical force is called the [________________]. - CORRECT ANSWER✅✅equilibrium potential
The difference between the membrane potential (Vm) and the equilibrium potential (Ex) for any given
ion is called [_____________]. - CORRECT ANSWER✅✅driving force
When current flow across the membrane in one direction exceeds current flow in the opposite
direction, it is called ___________. - CORRECT ANSWER✅✅rectification
Ion channels flux (transfer) ions across the membrane at rates of
, a.) 10^7-10^8 ions/sec
b.) 10^3-10^5 ions/sec
c.) 10^2-10^3 ions/sec
d.) 10^9-10^10 ions/sec - CORRECT ANSWER✅✅10^7-10^8 ions/sec
Driving Force is:
a.) equals the difference between the equilibrium potential (Ex) and the membrane potential (Vm).
b.) zero when the Vm = Ex
c.) is required for current to flow across the membrane
d.) All of the above - CORRECT ANSWER✅✅d.) all of the above
Ion channel activity is:
a.) Random
b.) Stochastic
c.) Probablistic
d.) All of the above - CORRECT ANSWER✅✅d.) all of the above
In voltage-gated channels, the S4 transmembrane segment functions as a _______ and the region
between S5 and S6 functions as the ________. - CORRECT ANSWER✅✅voltage sensor; pore
Regions of channel proteins that cross the membrane from one side (extracellular) to the other
(cytoplasmic) are called:
A.) membrane-spanning
B.) transmembrane segments
C.) extracellular loops
