Exam 1 Patho- NURS 8022/151 Q’s and
A’s
Negative Feedback - -Promotes stability; cancels out the original response.
Ex: High FSBS, increased insulin by the pancreas
-Positive Feedback - -Promotes a change in one direction; instability,
DISEASE. Ex: Blood clotting, platelet cascade
-Proteins - -Provide selectivity to a membrane
-Integral proteins - -channels, pores, carriers, enzymes, receptors, second
messengers
-Peripheral proteins - -Enzymes, intracellular, signal mediatiors
-ATP - -Converted to ADP to produce energy; chemical bonds between 2nd
and 3rd phosphate groups have abundant energy
-Simple/passive diffusion - -Occurs down a concentration gradient; from
HIGH to LOW concentration
-Simple/passive diffusion - -Diffuse from high to lower pressure; diffusion
will not occur if the membrane is non permeable to the molecule
-Factors that affect the net rate of diffusion - -1. Concentration difference
(high to low)
2. Electrical Potential (EMF)- charge difference on each side of the membrane
matters TOO!
3. Pressure difference (higher pressure results in increased energy)
-Osmosis - -Passive transport of fluid across a membrane; from an area of
low solute concentration to high solute concentration (high FLUID to low
FLUID)
-Primary Active Transport - -Molecules are "pumped" against ("uphill") a
concentration; DIRECT USE OF ENERGY
-Secondary Active Transport - -Trasport is driven by the energy STORED in
the concentration gradient of another molecule (Na+); INDIRECT USE OF
ENERGY
-Na+- K+ ATPase - -Carrier protein located on the plasma membrane of alll
cells; enzyme that converts ATP to ADP to release energy
, -Important role in regulating osmotic balance
-Requires one to two thirds of cells energy
-Ca2+ ATPase - -Maintains a low cystosolic Ca2+ concentration
-H+ ATPase - -- Found in parietal cells of gastric glands (HCl secretion) and
intercalated cells of renal tubules (controls blood pH)
- Concentrates H+ ions up to 1 million-fold
-Remember: Sodium Potassium Pump - -sodium is pumped out of the cell;
potassium is pumped in...
-Secondary Active Transport; Co-transport - -Co-transport: Substance is
transported in the same direction as the "driver" ion (Na+)
-Counter transport - -Substance is transported in the opposite direction as
the driver ion Na+
-How do cardiac glycosides increase cardiac contractility? - -Increase
intracellular Ca2+
-ungated Ion Channels - -determined by size, shape, distribution of charge
-Gated Ion Channels - --volgate (e.g.) Voltage dependent Na+ channels)
-Chemically (e.g. Nicotinic AcH receptor channels)
-Ion Channels - -Conductance depends on probability that channel is open.
-Equilibrium Potential - -the diffusion potential that exactly balances or
opposes the tendency for diffusion down the concentration difference.
-If a membrane were permeable to only K+ then... - -K+ would diffuse down
its concentration gradient until the electrical potential across the membrane
countered diffusion. (moving from inside the cell down its concentration
gradient to the outside of the cell).
-Potassium Nernst Potential - -Also called equilibrium potential; if the
membrane were only permeate to K+; the Vm would be -94mv.
-Sodium Nernst Potential - -If the membrane were only permeable to Na+
then the Vm would be +61mv.
-The Goldman Hodgkin Katz Equation - -The resting membrane potential is
closest to the equilibrium potential for the ion with the highest permeability!
A’s
Negative Feedback - -Promotes stability; cancels out the original response.
Ex: High FSBS, increased insulin by the pancreas
-Positive Feedback - -Promotes a change in one direction; instability,
DISEASE. Ex: Blood clotting, platelet cascade
-Proteins - -Provide selectivity to a membrane
-Integral proteins - -channels, pores, carriers, enzymes, receptors, second
messengers
-Peripheral proteins - -Enzymes, intracellular, signal mediatiors
-ATP - -Converted to ADP to produce energy; chemical bonds between 2nd
and 3rd phosphate groups have abundant energy
-Simple/passive diffusion - -Occurs down a concentration gradient; from
HIGH to LOW concentration
-Simple/passive diffusion - -Diffuse from high to lower pressure; diffusion
will not occur if the membrane is non permeable to the molecule
-Factors that affect the net rate of diffusion - -1. Concentration difference
(high to low)
2. Electrical Potential (EMF)- charge difference on each side of the membrane
matters TOO!
3. Pressure difference (higher pressure results in increased energy)
-Osmosis - -Passive transport of fluid across a membrane; from an area of
low solute concentration to high solute concentration (high FLUID to low
FLUID)
-Primary Active Transport - -Molecules are "pumped" against ("uphill") a
concentration; DIRECT USE OF ENERGY
-Secondary Active Transport - -Trasport is driven by the energy STORED in
the concentration gradient of another molecule (Na+); INDIRECT USE OF
ENERGY
-Na+- K+ ATPase - -Carrier protein located on the plasma membrane of alll
cells; enzyme that converts ATP to ADP to release energy
, -Important role in regulating osmotic balance
-Requires one to two thirds of cells energy
-Ca2+ ATPase - -Maintains a low cystosolic Ca2+ concentration
-H+ ATPase - -- Found in parietal cells of gastric glands (HCl secretion) and
intercalated cells of renal tubules (controls blood pH)
- Concentrates H+ ions up to 1 million-fold
-Remember: Sodium Potassium Pump - -sodium is pumped out of the cell;
potassium is pumped in...
-Secondary Active Transport; Co-transport - -Co-transport: Substance is
transported in the same direction as the "driver" ion (Na+)
-Counter transport - -Substance is transported in the opposite direction as
the driver ion Na+
-How do cardiac glycosides increase cardiac contractility? - -Increase
intracellular Ca2+
-ungated Ion Channels - -determined by size, shape, distribution of charge
-Gated Ion Channels - --volgate (e.g.) Voltage dependent Na+ channels)
-Chemically (e.g. Nicotinic AcH receptor channels)
-Ion Channels - -Conductance depends on probability that channel is open.
-Equilibrium Potential - -the diffusion potential that exactly balances or
opposes the tendency for diffusion down the concentration difference.
-If a membrane were permeable to only K+ then... - -K+ would diffuse down
its concentration gradient until the electrical potential across the membrane
countered diffusion. (moving from inside the cell down its concentration
gradient to the outside of the cell).
-Potassium Nernst Potential - -Also called equilibrium potential; if the
membrane were only permeate to K+; the Vm would be -94mv.
-Sodium Nernst Potential - -If the membrane were only permeable to Na+
then the Vm would be +61mv.
-The Goldman Hodgkin Katz Equation - -The resting membrane potential is
closest to the equilibrium potential for the ion with the highest permeability!
