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11
PART A
The Cardiovascular
System
PowerPoint® Lecture Slide Presentation by Jerry L. Cook, Sam Houston University
ESSENTIALS
OF HUMAN
ANATOMY
& PHYSIOLOGY
EIGHTH EDITION
ELAINE N. MARIEB
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
The Cardiovascular System
 A closed system of the heart and blood vessels
 The heart pumps blood
 Blood vessels allow blood to circulate to all
parts of the body
 The cardiovascular system delivers oxygen and
nutrients to cells and removes carbon dioxide
and other waste products
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
The Heart
 Location:
 Bony thorax between the lungs
 Pointed apex directed toward left hip
 About the size of your fist
 Heart is covered by a double membrane
called the Pericardium
 Serous fluid fills the space between the layers
of pericardium to prevent friction when heart
contracts
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
The Heart
Figure 11.1
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The Heart: Chambers
 Right and left side act as separate pumps
 Four chambers
 Atria (receiving chambers)
 Right atrium
 Left atrium
 Ventricles (pumping chambers))
 Right ventricle
 Left ventricle
Figure 11.2c
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
The Heart: Valves
 Valves allow blood to flow in only one direction
 Four valves:
 Atrioventricular valves between atria &
ventricles
 Bicuspid valve (left side)
 Tricuspid valve (right side)
 Semilunar valves between ventricle & artery
 Pulmonary semilunar valve
 Aortic semilunar valve
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Blood Vessels: The Vascular System
 Taking blood to the tissues and back
 Arteries: carry blood AWAY from heart
 Veins: carry blood back to heart
 Capillaries: small blood vessels
Figure 11.8a
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Blood Circulation
Figure 11.3
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
The Heart
 Heart valves open and close as blood pumps
through. Valves prevent backflow of blood.
 Valves are held in place by chordae
tendineae (“heart strings”)
 Heart muscle cells contract, without nerve
impulses, in a regular, continuous way
through electrical impulses –
 Sinoatrial node
 Pacemaker
 Atrioventricular node
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
The Heart: Associated Great Vessels
 Vena cava (large veins)
 Enters right atrium with oxygen poor blood
 Pulmonary (lung) arteries
 Leaves right ventricle with oxygen poor
blood sent to lungs to pick up more oxygen
 Pulmonary veins (four)
 Enter left atrium with oxygen rich blood
 Aorta
 Largest artery, leaves left ventricle with
oxygen rich blood for body tissues
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Filling of Heart Chambers – the Cardiac
Cycle
Right and left atria contract simultaneously;
Atria relax, then ventricles contract
Figure 11.6
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
The Heart: Regulation of Heart Rate
 Increase heart rate:
 Sympathetic nervous system (stress, crisis, BP)
 Hormones (Epinephrine, Thyroxine)
 Exercise, Decreased blood volume
 Decreased heart rate:
 Parasympathetic nervous system
 High blood pressure or blood volume
 Dereased venous return
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Major Arteries of Systemic Circulation
Figure 11.11
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Major Veins of Systemic Circulation
Figure 11.12
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Pulse
 Pulse – pressure
wave of blood
 Monitored at
“pressure points”
where pulse is
easily palpated
Figure 11.16
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Variations in Blood Pressure
 Normal Blood Pressure
 140–110 mm Hg systolic
 80–75 mm Hg diastolic
 Hypotension (low blood pressure)
 Low systolic (below 110 mm HG)
 Often associated with illness
 Hypertension (high blood pressure)
 High systolic (above 140 mm HG)
 Can be dangerous if it is chronic
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Anatomy
 Heart Beat – Lub Dub
Lub (closing of atrioventricular valves)
Dub (closing of pulmonary lunar valves)
 Illness/Issues of the Heart (Cardiovascular Sys)
Atherosclerosis: lipid (fat) deposits on arteries
Angina Pectoris: crushing chest pain, lack of
oxygen to heart
Myocardial Infarction: heart attack, lack of oxygen
to myocardium (heart muscle) can’t pump
Tachycardia: Rapid heart beat, over 100 beats
Bradycardia: Slowed heart beat, under 60 beats
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Anatomy
TEST CH 11 – TOMORROW, Pencil!
 In Text book p 386, Do Short Answer:
1, 3, 4, 5, 6, 7, 12, 13, 16, 17, 18, 19, 23, 30
DUE TODAY– Turn in end of class
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings