The Human Heart Functions of the Heart 1

The Human Heart

Functions of the Heart 1. Generating blood pressure 2. Routing blood • Heart separates pulmonary and systemic circulations 3. Ensuring one-way blood flow • Heart valves ensure one-way flow 4. Regulating blood supply • Changes in contraction rate and force match blood delivery to changing metabolic needs

Size, Shape and Location of the Heart • Size of a closed fist • Shape • Apex: Blunt rounded point of cone • Base: Flat part at opposite of end of cone • Located in thoracic cavity

Pericardium: a double membrane surrounding the heart

Heart Muscle Composition • Three layers of tissue 1. Epicardium: This membrane is the smooth outer surface of heart 2. Myocardium: Middle layer composed of cardiac muscle cell and responsible for heart contraction 3. Endocardium: Smooth inner surface of heart chambers

Heart Anatomy • Four chambers • 2 atria • 2 ventricles • Major veins • Superior vena cava • Inferior vena cava • Pulmonary veins • Major arteries • Aorta • Pulmonary artery or trunk

Heart Valves 1. Atrioventricular • Tricuspid • Bicuspid or Mitral 2. Semilunar • Aortic • Pulmonary • Function to prevent blood from flowing back

Blood Flow Through Heart

Systemic vs Pulmonary Circulation

Blood Flow through the Heart • https: //www. youtube. com/watch? v=7 Xaftd. E_h 60