NEURON FUNCTION SCRIPT COMPLETE
QUESTIONS AND CORRECT ANSWERS
GRADED A+
◉ looking at model 1
at what potential are the sodium ion gates closed
Answer: the sodium ion gates close when the membrane potential
reaches +35 mV
◉ At what potential are the potassium ion gates closed?
Answer: The potassium ion gates close when the membrane
potential reaches -80 mV
◉ Describe how the electrical signal in the neuron moves
Answer: the gates open one at a time from left to right in model 1.
the high concentration of sodium ions inside the cell moves from
left to right in model 1
◉ A. When the gated embedded proteins (either sodium or
potassium) close, do the sodium and
potassium ions remain on the side of the membrane that they are
on, or do they move back to
their original position?
, Answer: The sodium and potassium ions eventually move back to
their original position
◉ B. Propose a mechanism that the cell might use to accomplish
the change you describe in part A
Answer: The sodium and potassium ions move through embedded
proteins in the membrane to reinstate the resting membrane
potential
◉ C. Could another signal be sent down the length of the neuron
cell if the sodium ions and potassium ions were not returned to
their original position?
Answer: No, the neuron cannot transmit another signal until the
ions are returned because the concentration gradients for the ions
are going in the wrong direction
◉ Define depolarized
Answer: When an action potential is in progress the cell
membrane is depolarized. The potential difference between the
two sides of the membrane is decreased
◉ Define refractory period
Answer: After a sodium ion gate has been opened and closed it is
in a refractory period where the membrane potential in the
immediate vicinity is very low and the embedded protein cannot
be opened again. This is called hyperpolarizaton and and
repolarization
QUESTIONS AND CORRECT ANSWERS
GRADED A+
◉ looking at model 1
at what potential are the sodium ion gates closed
Answer: the sodium ion gates close when the membrane potential
reaches +35 mV
◉ At what potential are the potassium ion gates closed?
Answer: The potassium ion gates close when the membrane
potential reaches -80 mV
◉ Describe how the electrical signal in the neuron moves
Answer: the gates open one at a time from left to right in model 1.
the high concentration of sodium ions inside the cell moves from
left to right in model 1
◉ A. When the gated embedded proteins (either sodium or
potassium) close, do the sodium and
potassium ions remain on the side of the membrane that they are
on, or do they move back to
their original position?
, Answer: The sodium and potassium ions eventually move back to
their original position
◉ B. Propose a mechanism that the cell might use to accomplish
the change you describe in part A
Answer: The sodium and potassium ions move through embedded
proteins in the membrane to reinstate the resting membrane
potential
◉ C. Could another signal be sent down the length of the neuron
cell if the sodium ions and potassium ions were not returned to
their original position?
Answer: No, the neuron cannot transmit another signal until the
ions are returned because the concentration gradients for the ions
are going in the wrong direction
◉ Define depolarized
Answer: When an action potential is in progress the cell
membrane is depolarized. The potential difference between the
two sides of the membrane is decreased
◉ Define refractory period
Answer: After a sodium ion gate has been opened and closed it is
in a refractory period where the membrane potential in the
immediate vicinity is very low and the embedded protein cannot
be opened again. This is called hyperpolarizaton and and
repolarization
