biochemistry Flashcards
(18 cards)
whats a sarcomere
contractile unit in muscle
what are Z lines
neighbouring parallel lines that make up the sarcomere
whats an M line
line at the centre of the sarcomere where myosin myofilaments bind
whats the A band
the length of a myosin myofilament within a sarcomere
whats the H band
area adjacent to M-line, only thick filaments
whats the I band
adjacent to z line, thin filaments only
this shortens during contraction
how is Ca2+ removed from cells
pumped back into sarcoplasmiv reticulum via SERCA
moves out via NCX antiporter
stroke volume =
EDV - ESV
ejection fraction =
SV / EDV
blood pressure
CO X peripheral vascular resistance
mean arterial pressure =
diastolic BP + (1/3 pulse pressure)
chronotropy
affecting heart rate
dronotropy
affecting speed of conduction
inotropy
affecting force of contraction
what increases contractility
calcium
SNS - noradrenaline, adrenaline
increased body temp
increased T3 and T4
what decreases contractility
PNS - acetylcholine
low calcium levels
hyperkalemia
frank starlings law
higher the EDV, higher the SV
which of these will cause a decrease in left ventricular oxygen demand?
- increased afterload
- increased preload
- decrease in ventricular wall tension
- increase in blood viscosity
decrease in ventricular wall tension
