Guided Notes for Structure of the Heart
1. Heart Size – about 14 cm x 9 cm (the size of a fist). It is located in the __________________________ (space between
lungs, backbone, sternum), between the 2nd rib and the 5th intercostal space. The distal end of the heart is
called the _____________.
2. A _____________________ pericardium encloses the heart (like a bag) and has 2 layers:
(1) _________________ pericardium (inner layer)
(2) __________________ pericardium (outer, attached to diaphragm, sternum and vertebrae)
3. The ______________ cavity contains fluid for the heart to float in, reducing friction. The wall of the heart consists of
three layers:
1. __________________ – outer layer, reduces friction
2. ________________ – middle layer, mostly cardiac muscle
3. __________________ – thin inner lining, within chambers of the heart
4. Your heart is a ____________________ pump. Circulation is a double circuit: _______________________ (lungs only)
and ________________________ (rest of the body)
The heart has ______ chambers:
1. 2 ______________ – thin upper chambers that receive blood returning to the heart through the
_________________________ (Right and Left Atrium)
2. 2 ___________________– thick, muscular lower chambers. Receive blood from the ________________
above them. The ventricles force (pump) blood out of the heart through arteries. (Right and left ventricle)
The ______________________ separates the right and left sides of the heart.
5. The valves of the Heart allow ______-way flow of blood. There are ____ total valves.
2 _________________________ valves (AV) & 2 ________________________ valves (SV)
– Left Atrioventricular valve – also called the _________________ valve or ______________ valve.
Between left atrium and ventricle
– Right Atrioventricular valve – also called the ___________________ valve. Between right atrium and
Aortic Semilunar – or just ______________ valve. Between the left ventricle and the aorta
Pulmonary Semilunar, or just __________________ valve. Between the left ventricle and the aorta
6. ___________________ Circulation – delivers blood to all body cells and carries away waste, while
_____________________ Circulation – eliminates carbon dioxide and oxygenates blood (lung pathway).
7. There are three main types of blood vessels:
(1) _______________ - carry deoxygenated blood away from the tissues towards the heart
(2) _______________ - carry oxygenated blood from the heart and lungs to the rest of the body
(3) ________________- where the exchange of water and chemicals between tissue and blood occur
8. All blood vessels have three main layers:
(1) Tunica __________________ (innermost layer) - thinnest layer – provides a smooth surface to decrease
_______________________ to blood flow; this is the only layer found in ____________________________
(2) Tunica _________________ (middle layer)- thickest layer in __________________; only layer involved in
directly regulating blood ______________________
(3) Tunica _________________ (adventitia) (outermost layer) – thickest layer in veins; provides _____________
Name the valves.
5. (not a valve)