Overview + Anatomy Flashcards
Systemic circulation is arranged ___________
In parallel
Why is it important that systemic circulation is in parallel?
- Oxygenated blood visits only one organ before returning to pulmonary circultion, 2. Changes in blood flow to one organ doesnt affect other organs, 3. blood flow can be varied to match demand
Which circulation does not run in parallel?
Hepatic- large fraction of hepatic blood is from intestines
Layers of heart (from inside to outside)
Endocardium, myocardium, epicardium, Pericardium
Which part of the CV system is arranged in series?
The left and right heart- No direct connection, thus output must be closely matched
Which ventricle is thicker? Why?
Left- supplies higher pressure systemic circulation,does more work, uses more O2 than right.
Tricuspid valve location
between right atrium & right ventricle
Pulmonic valve location
between right ventricle & pulmonary artery
Mitral valve location
between left atrium & left ventricle
Aortic valve location
between left ventricle & aorta
What valves attach to papillary muscles by chordae tendonae?
Tricuspid and mitral- prevents valves from prolapsing into atria during ventricular contraction
What is a murmur?
Defective valves make unusual sounds
What is regurgitation?
Minor leakage
Describe the pathway of conduction in the heart
SA node (Wall of right atrium) > impulse spreads through atria by gap junctions > AV node (slows conduction to allow atrial contraction before ventricular) > Bundle of His > Left and right Bundle branches > Purkinje system (depolarizes ventricles)
What is the intrinsic activity rate of SA node?
100bpm
When does most coronary blood flow occur
Diastole- Compression of microvasculature occurs during systole
Right and left coronary arteries arise from _________
root of aorta
Left coronary artery bifurcates into _________ and _________, and it supplies ___________ and ___________
Left anterior descending artery and circumflex artery, supplies left atrium and left ventricle
Right coronary artery supplies________
right atrium and ventricle, posterior part of left ventricle
In general, coronary veins drain into ___________
coronary sinus (opens into right atrium near inferior vena cava)
Describe the blood flow pathway through the heart
Deoxygenated blood from systemic circulation > superior & inferior venae cavae, > right atrium (no valve) > tricuspid valve >right ventricle >pulmonic valve >pulmonary arteries > lungs > pulmonary veins > Left atrium > mitral valve > left ventricle > aortic valve >aorta.
What are the layers of arterial walls (from inside to outside) and describe them
Tunica intima (single layer of endothelial cells) > Tunica media (innervated vascular smooth muscle) > tunica adventitia (connective tissue made of collagen and elastin)
What is microcirculation and what is its function?
vasculature from the first-order arterioles to the venules. Site of gas, nutrient and waste exchange. Blood flow controlled by pressure gradient, constriction/dilation of arterioles and precapillary sphincters.
