Chapter 12 - The Cardiovascular System: The Heart

Atrioventricular valve

folds of fibrous tissue that allows one way flow of blood from atria into ventricles

Atrium

entry chamber

Cardiac cycle

Period between start of 1 heartbeat and beginning of the next

Cardiac output

perfusion/indicator of blood flow to the tissues & volume of blood ejected from a ventricle in 1 minute

Diastole

relaxation

Electrocardiogram

Electrical events of the heart travel through body

Endocardium

innermost layer, Covers inside of chambers and heart valves

Epicardium

outermost layer, Covers the outer surface of heart

Intercalated disc

specialized sites/junctions connecting cardiac muscle cells.

Myocardium

middle layer containing cardiac cells, forms bands that squeeze during contraction

Pericardium

serous membrane

Purkinje Fibers

special conducting muscle cells located in inner ventricular walls of heart

Sinoatrial node

cardiac pacemaker,

Systole

contraction of a chamber

ventricle

fluid filled cavity/hallow part of organ