1.

Sizes of normal hearts/function:

● Size: about the size of a man’s closed fist
● Function: The function of the heart, a muscular organ, is to pump enough blood to meet the body’s metabolic needs
● Beats 60 to 100 times per minute and circulates 4 to 8 liters of blood per/min ● Average person’s heart beats 90,000 times and pumps out about 6,000 liters of blood
★ Location of the heart: In the Thoracic Cavity, b/w the lungs in a cavity called the mediastinum, above the diaphragm, behind the sternum, and in front of the spine.
2.
3.

Location of Apex of Heart: Bottom of the heart (Pointy part that rests on diaphragm) Location of Base of Heart: Top of the Heart (Greater vessels emerge)

R|L
*Lies at an angle with the bottom pointing to the left

4.

Define Chordae Tendonae: (Read Function)

● Location: AV Valves (ventricular side; lower chamber)
● Function: (tendinous cords); are attached to papillary muscles and anchor the valve cusps (bicuspid & tricuspid) to keep the AV valves from flopping backward and allowing backflow of blood
5.

Define Papillary Muscles: (Read Function)

● Location: located in the ventricles of the heart
● Function: muscles that attach to the cusps of the atrioventricular valves (a.k.a. the mitral and tricuspid valves) via the chordae tendineae and contract to prevent inversion or prolapse of these valves
6.

Define Septum:
The heart is divided into right and left sides of the septum

● Location: Middle of the heart (divides it to left and right sides)
★ septum separating the atria is called the interatrial septum
★ septum separating the ventricles is called the interventricular septum
● Muscle: muscular band of tissue
7.

Function of Pericardial Fluid: A small amount of fluid is found between the layers of the pericardium(a double-walled sac that encloses the heart). This pericardial fluid minimizes friction of these layers as they rub against each other with every heartbeat.

8.

Function/ Location:

● Epicardium★ Function: Provides an outer protective layer for the heart; helps hold the other heart muscles close together
★ Location: the outermost layer of the heart. The coronary arteries run along this layer ● Myocardium★ Function: made of pure cardiac muscle fibers and does the work of contracting
★ Location: the middle and thickest layer
● Endocardium★ Function: lines the heart’s chambers and folds back onto itself to form the heart valves; regulates contraction of the heart
★ Location: the thin innermost heart layer
9.
Areas of Heart that get damaged during a Myocardial Infarction:
● Myocardium
10.

Pericardium-

● Function: Keeps the heart contained in the chest cavity, prevents the heart from overexpanding when blood volume increases, and limits heart motion.
● Location: a double-walled sac that encloses the heart.
11.

Blood Flow Through Heart:

*Veins bring blood to the heart (CO2 Blood)
-Pulmonary veins are the only veins that carry oxygenated blood
*Arteries bring blood to the body (O2)
-Pulmonary arteries are the only arteries to carry deoxygenated blood

Know Difference b/w Valves:
● Right AV Valve: Tricuspid
● Left AV Valve: Bicuspid/Mitral Valve

12.

How Valves Open/Close

★ Valves open and close based on changes in pressure; only open in the direction of the blood flow.
★ Blood flows down from atrium to ventricle and up from ventricle to aortic/pulmonic valves
★ Tricuspid/Mitral Valves Open downward only when the atrium’s pressure is higher than the ventricles pressure
★ Aortic/Pulmonic Valves Open upward only when the pressure in the ventricle exceeds that in the waiting aorta and pulmonary artery

VALVE CLOSURE IS RESPONSIBLE FOR THE SOUNDS MADE BY THE BEATING
HEART
13.

Function of the Valves:

***FUNCTION OF VALVES IS TO PREVENT BACKFLOW OF BLOOD
● SEMILUNAR VALVES- 3 half moon shaped cusps; separate ventricle from artery
★ Pulmonic Valve: Located b/w right