Ch 12 Cardiac Physiology Part 1 & 2 Flashcards
Cardiovascular system contains
Heart and blood vessels
Circulatory system contains
heart, blood vessels, and blood
3 blood vessel types
arteries, veins, capillaries
Pulmonary circulation bring blood from…
right ventricle to the lungs
Systemic circulation brings blood from…
Left ventricle to all tissues of the body
Flow equation
F=P/R
Pressure is the…
force exerted by blood measured in mmHg
How does blood flow directionally
Higher to lower pressure
Flow is…
Volume of blood moved per unit of time
Measure in Ml/min
Resistance is…
Measure of friction that impedes flow
Factors that determine resistance
Viscosity
Length
Radius
What is blood viscosity
Friction between molecules of a flowing fluid
Blood vessel radius is…
inversely proportional to resistance
Resistance equation
R=(8L)/(pir^4)
What are cardiomyocytes
Cardiac muscle cells that contract with every heart beat
What type of cells start the conducting system
Pacemaker cells
Electrical contact through cardiomyocytes occur via what
Gap junctions
Name the electrical signals in order
SA node
AV node
Bundle of his
Purkinje Fibers
Bundle of his passes through what
Interventricular septum towards the apex
Purkinje fibers are what
nerve like processes spread throughout myocardium
Sinus rhythm is triggered by what? and what is an adult’s typical bpm
Triggered by SA node
70-80 bpm
How often does the SA node fire
every 0.8 seconds
Ectopic focus is…
region of spontaneous firing other than the SA node
Nodal rhythm is what
heart rate set by AV node if SA node gets damaged
