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