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Introduction
The cardiovascular system consists of the heart and
thousands of miles of blood vessels. Refer to Concept
Maps- 14-1 and 14-2: The Heart. The heart is the -muscular
pump that forces the blood through a system of vessels
made of arteries, veins, and capillaries. These vessels
transport the blood, which carries oxygen, nutrients,
hormones, enzymes, and cellular waste to and from the
trillions of cells that make up our bodies. These cells need
oxygen and nutrients from digested food to make the
Chapter 14chemical energy (ATP) that allows the cells to function
properly. Enzymes assist in the chemical reactions inside
the cells, and waste products from these reactions must be
transported by the cardiovascular system to sites like the
lungs and kidneys for excretion from the body. The force to
transport the blood is provided by the cardiac muscle that
makes up the bulk of the heart.
The function of transportation of blood by the cardi-
ovascular system occurs 24 hours a day 7 days per week,
nonstop for 70, 80, or 90 years or more. This is possibleHeart (^)
(^) has a specific performs specific (^)
Structure enables Functions (^)
(^) includes (^)
(^) See Concept (^)
Conducting^ Chambers^ Walls^14 Map-2.^
system^
includes^ include^ include^ includes^
(^) separated (^)
by (^)
(^) AV node, (^) One-
(^) SA node AV bundle, (^) Ventricles (^) way Atria Endocardium Myocardium Epicardium (^)
Purkinje’s^ valves^ (visceral^
fibers^ layer)^
(^) signal blood blood (^)
travels to to flows (^)
coordinate^ through^
contraction of (^)
®^
initiates contraction of
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CONCEPT Map 14- 1 The
heart.. (^)