Cardiac Electromechanical Coupling DSA Flashcards
1
Q
Thick filaments are composed of what?
A
Myosin
2
Q
Thin filaments are composed of what?
A
Actin, troponin, and tropomyosin
3
Q
What is the function of tropomyosin?
A
It runs along the groove of twisted actin strands and functions to block the myosin binding site on the actin.
4
Q
What process occurs for tropomyosin to separate from the myosin binding sites on actin?
A
Ca binds to the troponin C subunits. This removes the tropomyosin inhibition and actin can now bind to myosin.
5
Q
The magnitude of the tension developed by myocardial cells is proportional to what?
A
The intracellular Ca concentration
6
Q
Inotropism is also known as what?
A
Contractility
7
Q
Contractility correlates directly with what?
A
The intracellular Ca concentration.
