Ch 17 - The Heart Flashcards
Right side
Received oxygen poor blood
Left side
Receives oxygenated blood from lungs
Right atrium
Received blood returning from systematic circuit
Left atrium
Received blood returning from pulmonary circuit
Right ventricle
Pumps blood through pulmonary circuit
Left ventricle
Pumps blood through systematic circuit
Base
Leans toward the right shoulder
Apex
Points towards left hip
Pericardium
Double-walked sad that surrounds heart
Two layers of the pericardium
Fibrous and serous
Fibrous pericardium
Protects and anchors heart
Serous pericardium layers
Parietal and visceral
Parietal layer
Lines internal surface of fibrous pericardium
Visceral layer
Epicardium (external surface of heart)
Two serous layers are separated by
Pericardial cavity
Four chambers
Two superior atria and two inferior ventricles
Atria
Receiving chambers
Auricles
Appendages that increase atrial volumbe
Superior vena cava
Returns blood from body regions above the diaphragm
Inferior vena cava
Returns blood from body regions below the diaphragm
Ventricles
The discharging chambers
Right ventricle
Pumps blood into pulmonary trunk
Left ventricle
Pumps blood into aorta
Two major types of valves
Atrioventricular and semilunar
Heart valves
Ensure unidirectional blood flow through heart
Two atrioventricular valves
Tricuspid and mitral; prevent back flow into atria when ventricles contract
Two semilunar valves
Pulmonary and aortic; prevent back flow from major arteries back into ventricles
Cardiac muscle cells
Striated, short, branched, interconnected; contain numerous mitochondria
Difference between cardiac and skeletal muscles
Some cardiac muscles are self-excitable; heart contracts as a unit; tetanic contractions can’t occur in cardiac muscles; the heart relies exclusively on aerobic respiration
How are the heart chambers different?
Atria are smaller and have thinner walls;
