Download the cardiovascular system

THE CARDIOVASCULAR SYSTEM
(Circulatory System)
HEALTH TERMS:
Plasma: The fluid in which the other parts of blood are suspended
Hemoglobin: the oxygen-carrying part of the blood/ protein compound rich in iron
Platelets: smallest type of blood cell/ cells that prevent the body’s loss of blood
Arteries: the vessels that carry blood away from the heart
Capillaries: the vessels that carry blood between arterioles & small vessels called venules/
responsible for the transfer of nutrients and oxygen for carbon dioxide and waste with
the body’s individual cells
Veins: vessels that return de-oxygenated blood toward the heart from the body’s organs &
tissues
Congenital: occurring at birth
FUNCTIONS of the CIRCULATORY SYSTEM:
 Maintains an internal environment in which all cells are nourished
 Pumps blood
 Carries oxygen and nutrients to the body’s cells
 Carries Carbon Dioxide and waste matter from your body’s cells to the lungs and liver
for removal
STRUCTURE of the CIRCULATORY SYSTEM:
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Hearto most important part of your body’s vital organs
o consists of special type of muscle called myocardium
o contracts rhythmically and automatically
 Chambers—make sure that blood flows in only one direction
 Thick central wall called septum
o Divides interior of heart into left and right sides
 Upper chambers called Atrium
o Receive blood into the heart by way of Veins
o Right Atrium serves as natural pacemaker—controls heart
rate
 Lower chambers called Ventricles
o Release blood to the lungs and body by way of Arteries
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Circulation
 Body’s oxygen depleted blood enters Right Atrium from the body via
the Vena Cava
 Blood travels from the Right Atrium to the Right Ventricle
 Body’s oxygen depleted blood leaves Right Ventricle to the lungs via
Pulmonary Artery
 Blood releases waste and carbon dioxide into the lungs
 Blood picks up oxygen and nutrients in the lungs
 Body’s oxygen rich blood leaves lungs and enters Left Atrium via
Pulmonary Vein
 Body’s oxygen rich blood leaves Left Ventricle to nourish and feed
body’s cells via Aorta
Vessels
o More than 60,000 miles of blood vessels in the body
o Three main types
 Arteries
 Largest blood vessels
 Carry blood away from the heart
 Thick flexible tubes that enable vessel to withstand high blood
pressure
 Arterioles branch directly off of Arteries and connect to capillaries
 Capillaries
 Smallest blood vessels
 Form a network throughout body’s organs and tissues
 Not always open to blood flow but respond to the body’s needs
o Plays role in regulating body’s temperature
 Are responsible for cellular exchange
o Oxygen & nutrients for Carbon Dioxide & cellular waste
o Carbon Dioxide & waste feed into venules
 Veins
 Venules join to form veins
 Made of thinner, flexible tubes with multiple valves
o Utilize surrounding muscular contraction to move blood
back to the heart
o Valves prevent back-flow
Blood
o Fluid that transports all of the substances that your body needs to sustain life
o Delivers oxygen, hormones, and nutrients to the cells and carries away the wastes
that the cells produce.
o Plays important role in body’s defence against infection
 Plasma
 55% of blood volume
 Made up of Water (92%), nutrients, salts, proteins, other
chemicals, and blood cells
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Platelets
 3% of blood volume
 Smallest type of blood cell
 Means “little plates”
 Initiate chain reaction that causes blood to clot
o When they come into contact with damaged vessel walls,
they become sticky and clump at the site of the injury
o Chemical reactions cause platelets to release fibrin—scab
making fibers that create a clot and harden
Red Blood Cells
 40% of blood volume
 contains hemoglobin
o binds with oxygen and releases the O2 into the tissues
o is the pigment that gives blood its red color
White Blood Cells
 2% of blood volume
 Principle role protects the body against infection & fight infection
when it occurs
 Larger than red blood cells in size; but far fewer in number
 Production increases when there is sickness in the body
o Some WBC surround and ingest invading pathogens
o Others form antibodies that create an immunity to second
attacks of diseases
 Measles & Chicken Pox
CARE of the CIRCULATORY SYSTEM:
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Most risk factors that affect Circ. System are within one’s control
Health choices and behaviors affect its health
o Avoid Smoking and second-hand smoke
o Maintain appropriate weight
 Obesity linked to high blood pressure and coronary heart disease
o Exercising regularly
 Aerobic Exercise
 At least 20 min./ 3x week
 Heart pumps more efficiently
 Improves circulation
o Eating healthfully
 Limiting intake of fried foods
 Avoid foods high in fat, cholesterol, and salt
 Increase intake of variety of healthy foods
o Get enough sleep
 At least 7-8 hours/ evening
o Schedule regular medical check-ups
PROBLEMS of the CIRCULATORY SYSTEM:
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High blood pressure
o The force of blood in the main arteries
o Rises and falls as the heart and muscles of the body cope with varying demands
 Stress,Exercise, Sleep
o Systolic / diastolic….. 120/ 80 = Normal
 Each time the ventricles contract there is a surge of blood into the arteries
creating the greatest amount of force that artery walls bulge—pressure is
at its greatest—Systolic Pressure…~110- 140
 As the ventricles relax and refill with blood, arterial pressure is at its
lowest—Diastolic Pressure …~70- 90
Congenital heart disease
o Caused by a disruption in the proper development of the heart before birth
o Covers a wide range of conditions
 Hole between two chambers of the heart
 Improperly functioning valves
 Blockage of blood flow
 Defect in the blood vessels that lead to or away from the heart
Heart murmur
o Abnormal sound in the heart beat
o Normal= lub dub; Murmur= lub dub dub
o Blood is forces through a smaller valve with greater force or a valve does not
close properly
o Medical Treatment depends on severity—some cure themselves; others require
surgery
Varicose veins
o Swollen and enlarged veins
o Develop when valves in veins are weakened and can not prevent backflow
o Can affect men and women of all ages
o Can be surgically treated
Anemia
o A condition in which the concentration of hemoglobin in the blood is below
normal levels
o Body does not receive sufficient amounts of oxygen
o Is a deficiency of iron in the diet—can be fixed by eating leafy green veggies,
dried fruits, enriched cereals, or iron supplements
Leukemia
o Any of several types of cancer resulting from abnormal production of WBC in
bone marrow
o Abnormal cells spill into other organs and interfere with their functions.
o Prevents bone marrow from producing RBC, Platelets and normal WBC
o Risk of Death from overwhelming infection or blood loss
o Bone Marrow transplants, Chemotherapy, and Radiation can slow disease process
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Hemophilia
o Inherited bleeding disorder caused by deficiency of a blood protein that is
essential to the process of blood clotting.
o Blood clots very slowly or not at all
o Bleeding can occur after injury or spontaneously
o Affects mainly males; although women can be carriers of the disease