Cardiovascular System: Structure of Heart

Heart Location

Located in mediastinum

Fibrous Pericardium

encloses the heart (like a bag) and has 2 layers

Visceral pericardium

inner layer encloses the heart

Parietal pericardium

outer layer encloses the heart

ericardial cavity

contains fluid for the heart to float in, reducing friction

Epicardium

outer layer of heart wall, reduces friction

Myocardium

middle layer of heart wall, mostly cardiac muscle

Endocardium

thin inner lining of heart wall, within chambers of the heart

mitral or bicuspid

between left atria and ventricle (Left Atrioventricular valve0

tricuspid valve

Between right atrium and ventricle (Right Atrioventricular valve)

Aortic Semiluna

Aorta valve

Pulmonary Semilunar

Pulmonary valve

Systemic Circulation

delivers blood to all body cells and carries away waste

Pulmonary Circulation

eliminates carbon dioxide and oxygenates blood (lung pathway)

Blood veins

carry deoxygenated blood away from the tissues towards the heart

Arteries

carry oxygenated blood from the heart and lungs to the rest of the body

Capillaries

where the exchange of water and chemicals between tissue and blood occur

Tunica Intima

thinnest layer – provides a smooth surface to decrease resistance to blood flow; this is the only layer found in capillaries

tunica media

thickest layer in arteries; only layer involved in directly regulating blood pressure

tunica externa

thickest layer in arteries; only layer involved in directly regulating blood pressure