Snapps week 1 Flashcards
if a cell shrinks, the solution is
hypotonic
internal virion proteins are coded by which gene
gag
pol encodes from
reverse polymerase
v-myc mimics
c-myc proto-oncogene in cell growth and division
total outside cells included
ECF AND 5th space for a total of 18L
p53 mutations are most often
missense
which substances will not dissociate in solution?
(NH2)2 CO
Urea
Glucose
what drug target to prevent refolding of SNARE
sec1
sec1 functions to
refold SNAREs into their active conformation by binding and acting on syntaxin
aldosteone acts on the ____, it increases ___
collecting tubule
K excretion
aldosterone is low in ____
diabetics
aldosterone is decreased by
ACE inhibitors and ARBs
95% of p53 mutations are caused by
inhibiting transactivation binding domain, so p53 can’t bind DNA
too many anti-acids can cause
Low pH facilitates of passive diffusion of plasma across the mucosal barrier
what always moves passively across membrane?
urea and water
FAP is ___ inherited
dominant
manifestations of VHL
- large vascular cell carcinomas
- angiomatosis retinae
- hemangiomas
which hyperkalemia treatment stimulates uptake of extracellular potassium into cells?
insulin and glucose
HPV function to stim cancer
inhibits p53 and RB
if cell vm= -40, concentration of Naout =140
Na in= 14
Na is being pumped into the cell because
vm= -40
E = log (140/14) = +60
A cell in a steady state contains 200mM of a neutral nonpermeating protein. The cell membrane is impermeable to Na+ but permeable to Cl-. If there is 200mM Na in the ECF, what is the total osmolarity, Na+ and Cl- concentrations inside the cell?
total osmolarity: 200
Na = 200
cl= 0
As a result of ketoacidosis, blood HCO3- concentration is reduced from 24 to 8mM. Hyperventilation causes pCO2 to drop to 15mmHg. What is the patient’s blood pH?
- 3 pH = 6.1 + log (8mM)/(.03x15) =
7. 34
A cell containing only water and 300mM of a non-permeating protein is placed in a solution of 600 non-permeating sucrose. The membrane is permeable to water. What will be the volume of the cell (relative to its initial volume) after all net fluxes have stopped?
cell will be 1/2 its initial volume
the cell will shrink to 1/2 its initial volume, at which point the osmolarity inside will equal the osmolarity outside, which is another way of saying that the concentration of water on the two sides is the same
SNAPs and syntax ins are located?
target membrane
An 8 year old boy presents to your office for increased work of breathing. His parents explain that he has been complaining of increased thirst and urination for the past 3 weeks. He has lost 8 pounds since his last visit and his breath smells slightly fruity. After doing initial blood work, you find a venous pH of 7.04. You proceed with a urine analysis. Which of the following findings is most likely?
increased K+
The increased levels of H+ will be cause H+ to be exchanged for K+
VHL inheritance
autosomal recessive
most serious symptoms of hypokalemia?
cardiac arrhythmia also Low BP high HR decreased appetite diarrhea low K
common to all SNARE protein
helical domain
most common cause of death in VHL patients today?
renal cell carcinoma
What results from insulin release from pancreatic B cells?
- increased storage of glycogen in liver
- decrease in lipolysis and gluconeogeneisis in liver
- inhibits ketone body formation
- increases fatty acid storage as triglycerides
- signals cellular uptake of glucose
A soldier is stranded and starving in the desert. Because of his starvation, he has become less capable of producing ATP. As a result his Na+/K+ transporter is affected. Which of the following effects would a compromised Na+/K+ pump have on his cells?
resting membrane potential moves toward sodium equilibrium potential
If a cell is a steady state has a Vm = -80 mV, and the concentration of H+ out = 50 nM, and H+ in = 100 nM, Which of the following must be true?
H is being pumped into the cell
Vm = -80 mV E = 60log (50/100) = -18 mV
Which of the following drugs have been shown to DECREASE serum K?
loop diuretics
how diuretics work?
diuretics increase excretion, so would decrease K ACE inhibitors and ARB (Retinoblastoma)s, NSAIDS, heparin, and drugs that contain K will increase blood potassium Dietary K also contributes
A cell that is homozygous for mutated RB (Retinoblastoma gene) is in S phase of the cell cycle. If a signal from outside the cell arrives to the plasma membrane in order to trigger inhibition of cell growth, which of the following will occur?
cell continues to divide because RB cannot be activated and inhibit cell growth
increased risk for cerebral edema are:
- administer bicarbonate quickly
- insulin quickly
- smaller than normal increase in Na
which would make hyperkalemia a more serious problem in a patient?
neuropathy
inheritance of RB?
autosomal recessive (because it requires 2 hits) with a dominant inheritance pattern (a single LOH will cause cancer)
If O2 level decrease, Hif1 alpha will _____
not be ubiquitinated and will promote vascularization.
in the presence of high CDK,
more cells will proceed into S phase
function of NSF?
hydrolysis of ATP to disassemble SNARe complex
A patient presents to your clinic with hyperkalemia caused by rhabdomyolysis. Why are you concerned about decreased kidney function?
myoglobin is toxic to kidneys
Suppose we have a cell that is permeable to Cl-, with a higher concentration of Cl in the ECF than in the cell. What will be the sign of the Cl equilibrium potential?
negative
a negative Ecl will be needed to repel C and keep it from diffusing into the cell down its concentration gradient
A cell containing 300 mosM of non-permeating ions is placed into a solution containing only 300 mosM solute with a reflection coefficient of 0.5. What will happen to the cell?
it will swell eventually
it will swell eventually. A reflection coefficient of .5 means that the solute can get into the cell half as easily as water. So at first, the ECF osmotic force = .5(600) = 300, and it will be isotonic. However, the solute will move into the cell and water will follow it. The cell will eventually swell and lyse.
Sorafenib and sunitinib are drugs that target which of the following?
VEGF-Receptor and PDGF-Receptor
A transporter in the proximal convoluted tubule of the kidney expels a bicaRB (Retinoblastoma)onate ion into the lumen of the tubule, while a chloride ion moves from the lumen into the cell. No ATP molecules are split in the process. Rather, energy from the downhill leak of sodium ions into the cell is what drives this transporter. Based on this information, you know this transporter must be which of the following?
exchanger
What is the best explanation for the rationale behind slow administration of insulin?
avoid rapid cellular fluid uptake
A cell sequesters amino acids in its cytoplasm via secondary active transport. What would happen to the concentration of amino acids if extracellular sodium is reduced so that Na inside the cell equals Na outside the cell?
net uptake of aa will stop
If [A-]/[HA] = 2, what percentage of the solution is deprotonated?
66%
During clysis, 300mosM glucose is administered subcutaneously to an infant. Why does a blister grow, but eventually disappear?
the reflection coefficient of glucose is greater than the reflection coefficient of NaCl.
K redistribution can cause hyperkalemia because K shifts from the cells into the ECF. Which of the following will promote potassium reuptake into cells?
beta agonist
venous blood is more ____ than arterial blood
acidic
What is the osmolarity of a 35M solution of KCl?
70 osM
1K, 1Cl = 2osM/L x 35L = 70 osM
If urea has a reflection coefficient of zero, what is the osmotic driving force for H20 to enter this cell? Na 100 (-) 100 Urea 100 (+) 0 Glucose 100 (-) 0
100 mosM If the reflection coefficient for urea =0 then it does not exert any osmotic force. Thus, there is a 100 mosM difference between ECF and ICF and water will move into the cell with an osmotic driving force of 100 mosM
A cell containing only water and 300mM of a non-permeating protein is placed in a solution of 300 mM non-permeating NaCl, and 600 permeating glycerol. The membrane is permeable to water. What will be the volume of the cell (relative to its initial volume) after all net fluxes have stopped?
cell will be 1/2 initial volume
the cell will shrink to 1/2 its volume. 300 mM NaCl - 600 mosM solution of Na and Cl ions. You can ignore glycerol completely.
If the RB (Retinoblastoma) protein is hypophosphorylated in a cell, what will happen?
cell will be arrested in G1 phase
