Heart Part 1 Flashcards
where is the heart.
posterior to sternum; extending left bwtn 2nd and 6th ribs.
In the middle mediastinum
How is the heart situated in body
Rotated left so Right half is anterior. Apex pointed down and left
Mediastium
spaces between the lungs
Pericardium
2 types of connective tissue surrounding heart:
Fibrous pericardium and Serous pericardium
Fibrous Pericardium
Thick layer of CT loosely surrounding heart
Adhered to sternum, diaphram and parietal pleura (lungs)
Serous pericardium
bursa; reduces friction between heart and adjacent structures. Pericardial cavity contains lubricant
- Visceral layer: invests outer heart (epicardium) - Parietal layer: outer layer adhered to inner surface of fibrous pericardium
Myocardium:
Parts of it and functions;
Cardiac muscle
Bulbospiral muscle: “wrings out” blood
Pectinate muscle: thin atrial cardiac muscle fibers
Trabeculae carnae: thick ventricular cardiac muscle fibers on inner surface. dense Smooth muscle bundles in wall of ventricle
Endocardium
CT lining interior surface
Epicardium
CT adhered to exterior surface=visceral pericardium
Functions of Right vs left sides of heart
Right side: transports deoxygenated venous blood to lungs
Left Side: transports oxengenated blood from lungs to peripheral tissues
Basic Function of AV and Semilunar valves and their location
Maintain one way blood flow through the heart
AV valve between atria and ventricles
semilunar vabetween ventricles and arteries
Bicuspid vs tricuspid valve
Bicuspid is left AV valve; Tricuspid is Right AV valve
Pulmonary valve vs Aortic valve
Both semi lunar vlaves:
Pulmonary conducts blood from RIGHT ventricle into pulmonary trunk(artery)
Aortic valve: LEFT ventricle into aorta
How does blood flow into Right Atrium?
Through Superior and inferior vena cava
Fossa Ovalis
Site of foramen ovale: a prenatal apeture that directs blood from Right to left atrium
What contracts to push blood into ventricles?
Pectinate muscle and vestigial auricle