2. The Heart Part Two Flashcards
What is the definition of heart rate?
pulse; number of times the cardiac cycle is repeated per minute
What is stroke volume?
amount of blood pumped with each systole
What is cardiac output?
total amount of blood pumped per minute
What is the equation for cardiac output?
CO = SV * HR
What are the two methods to increase cardiac output?
- increasing heart rate
- Frank-Starling Mechanism
What is a basic overview of the Frank-Starling Mechanism?
stretching the heart muscle by filling it with more blood in order to cause a larger contraction
What is venous return?
return of blood to the heart by the vena cava
What are the two methods to increase venous return?
- increase the total volume of blood in the circulatory system
- contraction of large veins can propel blood towards the heart
What are syncytium?
tissue in which the cytoplasm of different cells can communicate via gap junctions
What are T tubules?
involutions of the cardiac muscle cell membranes
What is the SA node?
sinoatrial node; special region in the right atrium that initiates each action potential
What is the pacemaker of the heart?
SA node
What is phase 4 of the SA node?
unstable resting potential
What is phase 0 of the SA node?
upstroke of the pacemaker potential
What is phase 3 of the SA node?
repolarization
