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Flashcards in lecture 32 - Cardiac muscle Deck (43)
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31

Noraepinephrin vs. noradrenaline

same thing mayyyyyyynnne

32

bmp without any neurotransmitters intervening

~100bpm

33

noradrenaline

- increases the rate of spontaneous depolarisation, which increases the heart rate

- increases the SR uptake of Ca2+ (more can be released) 

34

ACh

decreases rate of spontaneous depolarisation and decreases membrane potential

35

Starling's Law of The Heart

"As the resting ventricular volume is increased, the force of contraction is increased"

36

Na+/Ca2+ exchanger

voltage sensitive - stimulated by the repolarisation phase of the action potential.

37

sarcomere length in resting cardiac muscle is ____ and develop maximum force when stretched to ____

sarcomere length in resting cardiac muscle is _1.8μm_ and develop maximum force when stretched to _2.1μm_

38

Which numbers indicate:

a) where L-type Ca2+ channels open then close

b) where Na+ channels open and close

c) where K+ is pumped out

a) open at 1, close at 3

b) open at 0, close at 1

c) starts pumping out at 2, until a new AP initiates

39

which region of the curve is due to the I(funny current)

1

40

what is represented by each curve mayne?

1 = active tension in skeletal muscle

2 = active tension in cardiac muscle

3 = passive tension in cardiac muscle

4 = passive tension in skeletal muscle

41

Cardiac muscle is electrically __________ whereas skeletal muscle is electrically _________

Cardiac muscle is electrically _coupled_ whereas skeletal muscle is electrically _isolated_

42

increasing heart rate...

increases contractive force because there is less time for Ca2+ to be pumped out of the cell. Termed "automacity"

43

increased inotropy (presence of Noradrenaline) will...

increase active tension at any given length