Which of the following statements about the resting membrane potential is TRUE?
answer
It results, in part, from the concentration gradients for Na+ and K+
question
The resting membrane potential in a typical nerve cell is approximately
answer
-70 mV
question
Compared to the outside surface, the inside of a resting cell membrane is
answer
negatively charged
question
As the charge on the membrane of a typical neuron approaches 0 from -70 mV, the cell is
answer
only depolarizing
question
The ion that plays a key role in initiating electrical signals in neurons is
answer
Na+
question
Which of the following is NOT involved in creating the resting potential of a neuron?
answer
A. diffusion of potassium ions out of the cell
B. diffusion of sodium ions into the cell
C.* resting membrane permeability for sodium ions greater than potassium ions
D. resting membrane permeability for potassium ions greater than sodium ions
question
Gated channels for sodium ions may include
answer
-voltage gates, which respond to electrical signals.
-mechanical gates, which respond to pressure.
-chemical gates, which respond to ligands.
ALL!
question
to -50 mV from resting potential
answer
depolarization
question
to -70 mV from -50 mV
answer
repolarization
question
to -90 mV from resting potential
answer
hyperpolarization
question
to +30 mV from resting potential
answer
depolarization
question
Na+ enters the cell
answer
depolarization
question
Cl- enters the cell
answer
hyperpolarization
question
At rest, nerve cells have an unequal distribution of ions on either side of the cell membrane, producing the
answer
resting membrane potential
question
The cell membrane acts as a good
answer
electrical insulator
question
any value other than 0 mV, regardless of relationship to resting potential
answer
electrical polarization
question
Why is the resting membrane potential (Vm) approximately - 70 mV for most cells?
answer
Most membranes are 40 times more permeable to K+ than to Na+
question
The membrane potential of most cells ________.
answer
is negative, except when there is a change in membrane permeability to ions
Haven't found what you need?
Search for quizzes and test answers now
Quizzes.studymoose.com uses cookies. By continuing you agree to our cookie policy
