Download The Human Heart– Structure

1/22/13 The Human Heart– Structure Interesting Facts •  In your lifetime, your heart beats about 3 billion times without a single break • The aorta, the largest artery in your body, is almost the diameter of a garden hose • The heart pumps about 1 million barrels of blood during an average lifetime Anatomy of the Heart The Pericardium
Structure
•  a double wall sac covering the heart
Function
•  protects and anchors the heart
•  provides a friction-free environment
Figure 13.2 1 1/22/13 Anatomy of the Heart Think 4’s!
Four Chambers
•  Right and Left Atrium
•  Right and Left Ventricle
-separating the chambers is the septum
Four Vessels
•  Inferior/Superior Vena Cava and Aorta
•  Pulmonary Artery and Pulmonary Vein Four Valves
•  Tricuspid and Bicuspid Valve
•  Pulmonary and Aortic Semilunar Valve
Anatomy of the Heart Review Heart Anatomy Here Figure 13.4 Flow of Blood Through the Heart ü  Right side of the
heart pumps
deoxygenated blood to the lungs
ü  Pulmonary circuit
Figure 13.6 2 1/22/13 Flow of Blood Through the Heart ü  Left side of the heart
pumps oxygenated
blood to the body
ü  Systemic circuit
Figure 13.6 Flow of Blood Through the Heart ü  Atria pump together
ü  Ventricles pump together
ü  Valves between
chambers direct blood
flow in proper sequence
Click here to see how the blood flows through the heart! Figure 13.6 Pathway of Blood – Pulmonary and Systemic Circuits R. Atrium Pulmonary Artery R. Ventricle BCV PSLV Vena Cava Lungs Aorta ASLV L. Ventricle TCV L. Atrium Pulmonary Vein 3 1/22/13 Heart Valves u  Blood flows through the heart in one direction.
u  Heart valves open and close to prevent the backflow of blood within the heart.
u  The valves open and close in response to differences in blood pressure.
Figure 13.5 Heart Valves Atrioventricular (AV) valves (bicuspid and tricuspid)
u  Prevent backflow into atria when ventricles are contracting
u  Chordae tendinae and papillary muscles anchor and hold
valve flaps when closed
Heart Valves Semilunar (SL) valves
u  Prevent backflow into ventricles when ventricles relax
u  Flaps are small cups, shaped like ‘half moon’
u  Lack chordae tendinae of the AV valves, because they
close under less pressure
Click here to see how the valves work 4