GMS 6440 CORE MAIN EXAMINATION QUESTIONS AND
ANSWERS SURE A+
✔✔Nervous System - ✔✔Organs: Brain, spinal cord, peripheral nerves
Function: provide and interpret sensory info, coordinate activities of other systems
✔✔Female Reproductive System - ✔✔Organs: ovaries, uterus, vagina, mammary
glands
function: produce female sex cells, support embryo, provide milk
✔✔Menstrual cycle - ✔✔ovulation occurs around 14 days into cycle when LH surge
triggers release of single mature egg from ovary to go through fallopian tubes to the
uterus. If unfertilized, it is discharged and endometrium is shed (menstruation).
✔✔Distribution of Major Electrolytes - ✔✔Na+: 10:1 outside
K+: 25:1 inside
Cl-: 5:1 outside
HCO3-: 2:1 outside
Ca2+: micromolar inside. Thousand-fold greater outside.
Organic anions: 15:1 inside
✔✔channels vs transporters - ✔✔channels move water or ions and electrode
transporters are solute carriers or pumps
✔✔Permeability for passive diffusion - ✔✔-Ions (K+, Na+, HCO-, Ca2+, Cl-) do not
cross the membrane
-hydrophobic molecules (O2, N2, CO2) pass freely
-small, uncharged, polar molecules like glycerol can move to a small extent
-large, uncharged, polar molecules like glucose and sucrose do not cross by passive
diffusion
✔✔True or false: Channels only move things passively - ✔✔True
✔✔Parts of a channel: pore, selectivity filter, electric field sensor, gate - ✔✔Pore: spans
the whole membrane
Selectivity filter: allows specific charges or shapes through
Electric field sensors: sense the change in voltage or electric potential across the
membrane
gate: unlocks due to ligand-receptor binding
✔✔What are the four main ion channel types? - ✔✔Ligand-gated (lock-and-key),
voltage-gated (change in potential changes the field sensor to modulate gate), leak
(continuously open), and stretch-activated (perturbation of size and pore stretch)
, ✔✔Na+/K+ ATPase - ✔✔Carries out primary active transport. Made up of four subunits.
Upon hydrolysis of ATP, 3 Na+ out and 2 K+ in. Happens 100+ times a minute.
✔✔What are some of the functions of Primary Active Transporters? - ✔✔-pump
electrolytes out of one compartment into another
-solute gradients for osmotic stability
-ion gradients for bioelectricity
-ion gradients for secondary active transport
✔✔What is an example of a secondary active transporter? - ✔✔Na+/Glucose
transporter. Coupled to Na+/K+ ATPase. Movement of glucose is secondary to primary
active transporter.
✔✔pump-leak model - ✔✔key to remember: simultaneous but independent of each
other.
✔✔When is the concentration gradient equal and opposite to the electrical gradient? -
✔✔At equilibrium
✔✔What controls an electrolyte's movement across a membrane? - ✔✔Voltage and
concentration gradient (electrical + chemical)
✔✔What controls an electrolyte's electrochemical equilibrium potential? -
✔✔Concentration and degree of permeability of the membrane to that species
✔✔What is the equilibrium potential of K+ and Na+? - ✔✔-100 mV and +65 mV
✔✔What is the equilibrium potential of a cell and where does it come from? - ✔✔-90 mV
and comes mostly from that of K+
✔✔What is metabolic acidosis? - ✔✔excessive pH drop in the extracellular fluid which
results in a buildup of K+ in the ECF --> hyperkalemia ( >6.5mM K+).
To correct: enhance Na+/K+ ATPase by injecting insulin
✔✔What is rhabdomyolysis? - ✔✔A breakdown of muscle tissue that releases excess
K+ in the ECF leading to hyperkalemia ( >6.5mM K+). K+ then influxes into the cell and
causes the potential to depolarize to -20 mV.
✔✔How much of body weight is water?How much is found in ICF and ECF? - ✔✔60%
of body weight is water.
40% of that is in ICF and 20% is in ECF (75% of ECF is interstitial fluid and 25% is
plasma)
✔✔Can proteins travel through the capillary wall? - ✔✔NO
ANSWERS SURE A+
✔✔Nervous System - ✔✔Organs: Brain, spinal cord, peripheral nerves
Function: provide and interpret sensory info, coordinate activities of other systems
✔✔Female Reproductive System - ✔✔Organs: ovaries, uterus, vagina, mammary
glands
function: produce female sex cells, support embryo, provide milk
✔✔Menstrual cycle - ✔✔ovulation occurs around 14 days into cycle when LH surge
triggers release of single mature egg from ovary to go through fallopian tubes to the
uterus. If unfertilized, it is discharged and endometrium is shed (menstruation).
✔✔Distribution of Major Electrolytes - ✔✔Na+: 10:1 outside
K+: 25:1 inside
Cl-: 5:1 outside
HCO3-: 2:1 outside
Ca2+: micromolar inside. Thousand-fold greater outside.
Organic anions: 15:1 inside
✔✔channels vs transporters - ✔✔channels move water or ions and electrode
transporters are solute carriers or pumps
✔✔Permeability for passive diffusion - ✔✔-Ions (K+, Na+, HCO-, Ca2+, Cl-) do not
cross the membrane
-hydrophobic molecules (O2, N2, CO2) pass freely
-small, uncharged, polar molecules like glycerol can move to a small extent
-large, uncharged, polar molecules like glucose and sucrose do not cross by passive
diffusion
✔✔True or false: Channels only move things passively - ✔✔True
✔✔Parts of a channel: pore, selectivity filter, electric field sensor, gate - ✔✔Pore: spans
the whole membrane
Selectivity filter: allows specific charges or shapes through
Electric field sensors: sense the change in voltage or electric potential across the
membrane
gate: unlocks due to ligand-receptor binding
✔✔What are the four main ion channel types? - ✔✔Ligand-gated (lock-and-key),
voltage-gated (change in potential changes the field sensor to modulate gate), leak
(continuously open), and stretch-activated (perturbation of size and pore stretch)
, ✔✔Na+/K+ ATPase - ✔✔Carries out primary active transport. Made up of four subunits.
Upon hydrolysis of ATP, 3 Na+ out and 2 K+ in. Happens 100+ times a minute.
✔✔What are some of the functions of Primary Active Transporters? - ✔✔-pump
electrolytes out of one compartment into another
-solute gradients for osmotic stability
-ion gradients for bioelectricity
-ion gradients for secondary active transport
✔✔What is an example of a secondary active transporter? - ✔✔Na+/Glucose
transporter. Coupled to Na+/K+ ATPase. Movement of glucose is secondary to primary
active transporter.
✔✔pump-leak model - ✔✔key to remember: simultaneous but independent of each
other.
✔✔When is the concentration gradient equal and opposite to the electrical gradient? -
✔✔At equilibrium
✔✔What controls an electrolyte's movement across a membrane? - ✔✔Voltage and
concentration gradient (electrical + chemical)
✔✔What controls an electrolyte's electrochemical equilibrium potential? -
✔✔Concentration and degree of permeability of the membrane to that species
✔✔What is the equilibrium potential of K+ and Na+? - ✔✔-100 mV and +65 mV
✔✔What is the equilibrium potential of a cell and where does it come from? - ✔✔-90 mV
and comes mostly from that of K+
✔✔What is metabolic acidosis? - ✔✔excessive pH drop in the extracellular fluid which
results in a buildup of K+ in the ECF --> hyperkalemia ( >6.5mM K+).
To correct: enhance Na+/K+ ATPase by injecting insulin
✔✔What is rhabdomyolysis? - ✔✔A breakdown of muscle tissue that releases excess
K+ in the ECF leading to hyperkalemia ( >6.5mM K+). K+ then influxes into the cell and
causes the potential to depolarize to -20 mV.
✔✔How much of body weight is water?How much is found in ICF and ECF? - ✔✔60%
of body weight is water.
40% of that is in ICF and 20% is in ECF (75% of ECF is interstitial fluid and 25% is
plasma)
✔✔Can proteins travel through the capillary wall? - ✔✔NO
