Body SystemsThe Cardiovascular System
Functions of the CV System
Delivering Materials◦Picks up glucose to be used for energy◦Continually pumps blood
Removing Wastes◦CO2 is released as waste product in energy
production – taken to lungs to be exhaledFighting Disease
◦Cells that attack microorganisms◦Substances that seal cuts to prevent entry
The Heart
Structure of the Heart◦Left Side vs Right Side
Oxygenated vs deoxygenated blood
◦Chambers Atria: upper chambers; receive blood entering the heart Ventricle: lower chambers; pumps blood out of the
heart
◦Valves Between atrium and ventricle Allow blood to pass in one direction
The Heart
Structure of the Heart
The Heart
Your Heartbeat◦Phase 1: heart relaxes – atria fill◦Phase 2: heart contracts – blood pumped
Atria contract – blood to ventricles Ventricles contract – blood into large vessels to
rest of body◦Lub-Dub Sound
Valves between atria and ventricles Valves between ventricles and large vessels
The Heart
Your Heartbeat◦Regulated by the PACEMAKER◦Average resting heart rate (RHR) is 70-80◦Speeds up during exercise to meet increased
demands of sugar and oxygen.
The Blood Vessels
Arteries◦Carry blood away from the heart◦Carry oxygen-rich blood (except from heart to
lungs)◦Thick walls – strong and flexible◦When ventricles contract, blood is pumped into
the arteries◦When feeling for a pulse you are feeling for an
artery to expand.
The Blood Vessels
Capillaries◦Branch off from the smallest arteries◦Oxygen and dissolved substances diffuse
through walls and into cells◦Waste products (CO2) diffuses into the blood
The Blood Vessels
Veins◦Large, thin-walled◦Carry blood to the
heart◦Skeletal muscle
contractions squeeze blood back to heart
◦Valves prevent backward flow
The Blood Vessels
Measuring Blood Pressure◦The force with which blood pushes against the
walls of your blood vessels.◦Sphygmomanometer – used to measure
The Blood Vessels
Blood Pressure◦Normal: 90/60 to 119/79◦Low: medications, dehydration, allergies◦High: 140/90 – hypertension◦Systolic Pressure: pressure caused when
heart’s ventricles contract◦Diastolic Pressure: pressure when ventricles are
relaxed
The Blood
4-6 quarts of blood circulatingComplex tissue consisting of cells and cell
pieces in watery solution
The Blood
Plasma◦Straw colored liquid component◦55% of blood◦Mostly water; nutrients, hormones, and salts◦Carry wastes – urea to kidneys
Red Blood Cells (RBC’s)◦Carry oxygen from lungs to rest of body◦Contain hemoglobin – iron containing
substance for oxygen binding
The Blood
White Blood Cells (WBC’s)◦Larger than RBC’s but there are less◦Help protect against disease and foreign
substancePlatelets
◦Cell fragments used in clotting process
The Blood
Blood Types◦Determined by protein on surface of RBC◦Rh positive and negative
Transfusions◦If a patient is given the wrong blood the blood
will clump together in blood vessels
Cardiovascular Diseases
Hypertension◦Damages blood vessel walls◦Heart must work harder – may weaken and
eventually fail to pump blood◦Known as the silent killer◦Control with weight loss, exercise, low sodium
Heart Attack and Stroke◦Arteries thicken and blood flow is constricted◦Cells don’t receive adequate oxygen or clots
form
Cardiovascular Diseases
Blood Cholesterol◦Body produces, take in through animal products◦Transported by lipoproteins◦Low-Density Lipoproteins (LDL): carry
cholesterol for use in the body; “bad cholesterol” because it can lead to plaque
◦High-Density Lipoproteins (HDL): pick up excess cholesterol and take it to the liver; “good cholesterol”
◦ATHEROSCLEROSIS: plaque build-up; too much LDL, not enough HDL
Cardiovascular Diseases
Heart Murmur: an extra sound; sometimes disappear with no treatment
Opening in Heart Wall: ALL babies have before birth – problem when it doesn’t seal between two atria
ARRHYTHMIA: irregular heartbeat
Keeping Healthy
Exercise◦60 minutes most days◦Strengthen heart; decrease BP; decrease
stress; increase HDLDiet
◦Limit fried, processed, and animal productsAvoid Smoking
◦Tobacco damages blood vessels
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