Heart Flashcards
layers of heart
- tunica intima: endocardium
- tunica media: myocardium
- adventitia: epicardium
endocardium
- lined by endothelium that is continuous with vessels that enter the heart
- subendothelial layer: collagen, dense fibroelastic CT
- subendocardial: loose CT connected to myocardium; blood vessels, nerves, & purkinje fibers
myocardium
cardiac muscle tissue with deep (circular) & superficial layers (spiral)
epicardium
- outermost layer formed by mesothelial cells
- inner layer of loose CT & adipose tissue, coronary blood vessels
fibrous skeleton
skeleton composed of dense irregular CT
septum membranaceum
fibrous portion of IV septum
annuli fibrosi
fibrous rings around origins of pulmonary arteries, aorta, & atrioventricular canals
trigona fibrosa
fibrous tissue between arterial foramina & atrioventricular canals
atrioventricular valves
tricuspid &mitral; connected to papillary muscles of ventricles by fibrous cords called chordae tendineae
semilunar valves
between ventricles & aorta & pulmonary arteries
what kinds of tissue layers do valves have?
dense and loose CT surrounded by endothelium
sinoatrial node
pacemaker of heart; contains modified cardiac muscle cells around nodal artery
atrioventricular node
lies beneath endocardium in right atrium; forms common stem called bundle of His
atrioventricular bundle of His
formed by purkinje fibers; penetrates skeleton & branches to left & right
purkinje fibers
modified muscle cells that are filled with glycogen