the membrane that lines the cavities of the heart and forms part of the heart valves, inner layer of the heart wall consisting of epithelium and connective tissue as well as some specialized muscle tissue
the middle muscular layer of the heart wall - the thickest and pumps blood through the vessels
-have a singular nucleus
-branching of muscle fibers
these fibers are interwoven so that stimulation that causes the contraction of one fiber results in the contraction of a whole group. The intercalated disks and the branching cellular networks allow for the cardic muscles to contract in a coordinated manner
Functions of the Myocardium
the two upper chambers of the heart. There is a right atrium (which receives unoxygenated blood returning from the body) and a left atrium (which receives oxygenated blood returning from the lungs).
receives oxygen-poor blood from all tissues, except the lungs, through the superior and inferior venae cavae
the chamber on the right side of the heart that receives venous blood from the right atrium and pumps it into the pulmonary trunk
the chamber on the left side of the heart that receives arterial blood from the left atrium and pumps it into the aorta
Tricuspid valve - prevents blood from flowing back up into the right atrium when the right ventricle contracts - SYSTOLE
Right AV valve
bicuspid or mitral valve - prevents blood from flowing back upinto the left atrium when the left ventricle contracts - SYSTOLE
Left AV valve
valve with 3 half moon shaped cusps - prevents blood from flowing back into the right ventricle when the right ventricle relaxes - DIASTOLE
Pulmonary semi-lunar valve
valve with 3 half moon shaped cusps - prevents blood from flowing back into the left ventricle when the left ventricle relaxes - DIASTOLE
Aortic semilunar valve
the contraction of the chambers of the heart (especially the ventricles) to drive blood into the aorta and pulmonary artery
the widening of the chambers of the heart between two contractions when the chambers fill with blood, The stage of the heart cycle in which the heart muscle is relaxed, allowing the chambers to fill with blood.
atrial systole/ventricular diastole, ventricular systole/atrial diastole, brief complete diastole
the amount of blood pumped out by the ventricles in a given period of time, Stroke Volume X Heart Rate
a specialized bit of heart tissue that controls the heartbeat, the heart's pacemaker, located in the wall of the right atrium
neurological tissue in the center of the heart that receives and amplifies the conduction of impulses from the SA node to the bundle of His
fibers in the ventricles that transmit impulses to the right and left ventricles, causing them to contract
consists of anterior, middle, and posterior divisions that distribute electrical impulse generated by the sa node throughout the right and left atria to the artioventriuclar node
originates in an irritable automaticity focus that fires spontaneously, producing a beat earlier than expected in the rhythm
a bundle of modified heart muscle that transmits the cardiac impulse from the atrioventricular node to the ventricles causing them to contract
Bundle of his
the ability to respond to demands (exercise, stress, hypovolemia) by altering cardiac output threefold or fourfold.
supplies blood to the muscles of the heart to meet the high oxygen and nutrient demands of the cardiac muscle cells - blood vessels that supply the heart
a noninvasive diagnostic procedure that uses ultrasound to study to structure and motions of the heart
n this test a long, thin tube is inserted into the patient's body to inject a special dye, which can show narrowed areas in arteries due to plaque buildup and find other problems.