BIO 350 Exam 1 Questions With Complete Solutions
-A charged membrane results in a greater concentration
difference between ions.
-Ex: if membrane is negative, more Cl- ions will be repelled to
outside of membrane. Correct Answers How does a charged
membrane affect ion concentration and osmolarity?
-At rest, neuron has a resting potential of -70 mV. The interior
of the cells is negative.
-Stimulus- Changes membrane potential
Depolarization is when the membrane potential becomes more
positive.
-Opening of the channels that let Na+ flow into the cell.
-Happens at action potential.
Repolarization- A set of voltage gated potassium channels open,
allowing potassium to rush out of the cell down its
electrochemical gradient.
-Opens at peak.
-K+ leaves the cells causing it to become more negative.
-Stop Na+ from coming in and increase K+ going out.
Hyperpolarization is when the membrane potential becomes
more negative.
-Potassium channels are slow and stay open for a while causing
the action potential to go below resting membrane.
,-Channels slowly start to close and return back to resting
membrane potential. Correct Answers Explain the process of
hyper polarization and depolarization
-By blocking Na+ with TTX one can better understand the
relation of RMP and the equilibrium potential of potassium as
external K+ is increased.
-When voltage gated K+ channels are opened, the membrane
potential begins to decrease, and the current outward the cell is
increased. The cell membrane is more permeable to potassium
compared to Na+ and Cl-, making it a large contributor to the
negative resting membrane potential.
-Also the voltage gated K+ channels are slow closing, allowing
the MP to become hyper polarized.. Correct Answers Why is
RMP (resting membrane potential) following the equilibrium
potential of potassium as external K+ concentration is
increased?
-Carrier binds to one side
-Channel is flipped
-Carrier released on other side. Correct Answers How does a
carrier induce a conformational change?
-Current carried by K+ would increase up in the direction
outward.
-This means that K+ is being pumped out of the cell
-Would create a downward action potential on a membrane
potential graph.
-Current carried by Na+ would decrease in the direction inward.
-This means that Na+ is being pumped into the cell.
,-Would create an upward action potential on a membrane
potential graph. Correct Answers What would the graph for a
current of K+ look like? Na+?
-Cytoplasm
-2 ATP Correct Answers Glycolysis- Which specific region in
a cell does this take place and how many new ATP are produced
by the use of one glucose molecule?
-Electron acceptors
-Oxidation-reduction Correct Answers Energy is released
when electrons are transferred from high energy bonds to
_______________ in _____________________ reactions.
-For multiple ions
-Measures the permeability
-Better fits observations
-When potassium is low, it doesn't follow the linear curve for
the Nernst equation, because there is a sodium gradient that
affects the membrane potential.
-The Na+ leak channels increase the membrane potential.
Em (K, Na, Cl) = (RT/F) ln ( Correct Answers What is the G-
H-K equation?
-Glutamate binds
-Na flows out; K flows in
-Kick of Mg2+ plug on NMDA receptors
-Next stimulus can be activated
, -Can cause long-term affects on cell. Correct Answers How
does AMPA depolarize?
-Glutamate exits nerve terminal through vesicle.
Once released,
-Glutamate can diffuse away
-Presynaptic glutamate transport back into nerve terminals
-Glia takes glutamate back up.
-Glutamate is converted into glutamine once in glia cell
-Glutamine leaves glia cell into nerve terminal through
glutamine transporters.
-Glutamine is then converted back into glutamate
-Glutamate enters vesicle again for release
Glutamine Transporters
-Nerve terminal
-Glia
-Vesicle Correct Answers Explain the process of glutamate in
neurotransmitter release.
-Insert current (I)
-Observe voltage (v)
Rise Tau
-Time it takes to reach 63% of the maximum amplitude
observed on membrane voltage curve produced.
Decay Tau
-A charged membrane results in a greater concentration
difference between ions.
-Ex: if membrane is negative, more Cl- ions will be repelled to
outside of membrane. Correct Answers How does a charged
membrane affect ion concentration and osmolarity?
-At rest, neuron has a resting potential of -70 mV. The interior
of the cells is negative.
-Stimulus- Changes membrane potential
Depolarization is when the membrane potential becomes more
positive.
-Opening of the channels that let Na+ flow into the cell.
-Happens at action potential.
Repolarization- A set of voltage gated potassium channels open,
allowing potassium to rush out of the cell down its
electrochemical gradient.
-Opens at peak.
-K+ leaves the cells causing it to become more negative.
-Stop Na+ from coming in and increase K+ going out.
Hyperpolarization is when the membrane potential becomes
more negative.
-Potassium channels are slow and stay open for a while causing
the action potential to go below resting membrane.
,-Channels slowly start to close and return back to resting
membrane potential. Correct Answers Explain the process of
hyper polarization and depolarization
-By blocking Na+ with TTX one can better understand the
relation of RMP and the equilibrium potential of potassium as
external K+ is increased.
-When voltage gated K+ channels are opened, the membrane
potential begins to decrease, and the current outward the cell is
increased. The cell membrane is more permeable to potassium
compared to Na+ and Cl-, making it a large contributor to the
negative resting membrane potential.
-Also the voltage gated K+ channels are slow closing, allowing
the MP to become hyper polarized.. Correct Answers Why is
RMP (resting membrane potential) following the equilibrium
potential of potassium as external K+ concentration is
increased?
-Carrier binds to one side
-Channel is flipped
-Carrier released on other side. Correct Answers How does a
carrier induce a conformational change?
-Current carried by K+ would increase up in the direction
outward.
-This means that K+ is being pumped out of the cell
-Would create a downward action potential on a membrane
potential graph.
-Current carried by Na+ would decrease in the direction inward.
-This means that Na+ is being pumped into the cell.
,-Would create an upward action potential on a membrane
potential graph. Correct Answers What would the graph for a
current of K+ look like? Na+?
-Cytoplasm
-2 ATP Correct Answers Glycolysis- Which specific region in
a cell does this take place and how many new ATP are produced
by the use of one glucose molecule?
-Electron acceptors
-Oxidation-reduction Correct Answers Energy is released
when electrons are transferred from high energy bonds to
_______________ in _____________________ reactions.
-For multiple ions
-Measures the permeability
-Better fits observations
-When potassium is low, it doesn't follow the linear curve for
the Nernst equation, because there is a sodium gradient that
affects the membrane potential.
-The Na+ leak channels increase the membrane potential.
Em (K, Na, Cl) = (RT/F) ln ( Correct Answers What is the G-
H-K equation?
-Glutamate binds
-Na flows out; K flows in
-Kick of Mg2+ plug on NMDA receptors
-Next stimulus can be activated
, -Can cause long-term affects on cell. Correct Answers How
does AMPA depolarize?
-Glutamate exits nerve terminal through vesicle.
Once released,
-Glutamate can diffuse away
-Presynaptic glutamate transport back into nerve terminals
-Glia takes glutamate back up.
-Glutamate is converted into glutamine once in glia cell
-Glutamine leaves glia cell into nerve terminal through
glutamine transporters.
-Glutamine is then converted back into glutamate
-Glutamate enters vesicle again for release
Glutamine Transporters
-Nerve terminal
-Glia
-Vesicle Correct Answers Explain the process of glutamate in
neurotransmitter release.
-Insert current (I)
-Observe voltage (v)
Rise Tau
-Time it takes to reach 63% of the maximum amplitude
observed on membrane voltage curve produced.
Decay Tau
