Membranes Flashcards
to eat nice food
Hyperkalemia explain
High plasma potassium
Hypokalemia explain
low plasma potassium
What is Ventricular fibrillation
medical emergancy
What is Asystole
flat line
What could be a cause of Hypokalemia
excessive K+ loss in urine
What can hyperkalemia cause
can cause cardiac arrhythmias
What determines cellular excitability
membrane potential
What is the membrane potential largely set by
gradient of K+ across the cell membrane
What closes very slowly
H gate (inactivation gate)
What is an inactive ion channel
H gate is closed
What opens an ion channel
action potential
What phase gives the cardiac cycle its long action potential
Plateu phase
The amount of negative charge to ballance the equilibrium equation is called
Nernst equation
Em = (RT/zF) * ln(PK . aKo/aKi + PNa . aNao/aNai + PCl . aCli/aClo)
what equation is this
who gives a fuck
What causes the membrane potential to be depolarised
Na
Most cells in the heart are depolarised by
Na currents
What cells are not depolarised in the heart by Na currents
nodal cells
What does the refractoriness cause
the ventricles to refill with blood before onset of next contraction
What are calcium channels
L type
Where are T-type Ca channels located
pacemaker cells
In hyperkalaemia what happens to the resting potential
lowers the depolarisation so we get action potentials when we don’t want them
