Circulatory System Overview Includes heart, blood, and blood vessels Functions of the Circulatory System (CS) Internal transportation system Delivers O2 and nutrients to cells Removes CO2 and other wastes from cells Heart pumps blood throughout the body

Circulatory System Circulation (Movement of blood) Coronary circulation: the flow of blood to and from the tissues of the heart Pulmonary circulation: the heart pumps oxygen-poor blood to the lungs where it is oxygenated and returned to the heart Systemic circulation: oxygen-rich blood flows from the heart to the organs and tissues of the body, and oxygen-poor blood returns to the heart from the body

The Circulatory System (DRAW) Systemic Pulmonary

Heart Septum The heart is divided into two sides by the septum Septum – A thick wall of tissue that separates the heart into left & right sides Prevents oxygen-rich blood from mixing with oxygen-poor blood Septum

Right Atrium Left Atrium There are four chambers in the heart Two upper chambers are called atria Receive blood from body and lungs Right Atrium Left Atrium

Right Ventricle Left Ventricle Two lower chambers called ventricles Pump blood to body and lungs Right Ventricle Left Ventricle

The atrium & ventricles on the right have oxygen-poor blood returning from the body

The atrium & ventricles on the left have oxygen-rich blood returning from the lungs

Blood flows in one direction from atrium to ventricle and is controlled by one-way valves

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Blood Vessels (3 Main Types) A. Arteries Carry blood AWAY from the heart to tissues and organs. Thick walled and muscular WHY? The Aorta is the largest artery, & carries blood from the heart to the rest of the body. Artery Capillary Vein

Capillaries Connect veins & arteries Walls are very thin and porous to exchange materials What materials? Artery Capillary Vein Blood cells pass thru most caps in single file. Blood doesn’t actually enter tissue space. Nutrients and waste

Veins Carry blood to the heart. Thin-walled and muscular. Many are located near and between skeletal muscles (WHY?) Large veins contain valves to prevent backflow of blood. Artery Capillary Vein

Force of blood on the walls of blood vessels Blood Pressure Force of blood on the walls of blood vessels Highest in arteries, lowest in veins Rises and falls with heart beat Normal is below 120/80 First number is systolic (blood is being pumped) Second number is diastolic (heart refills w/blood) 120-139 is prehypertension; >140 is hypertension

Blood General information: Human body contains 4-6 liters Carries oxygen (lungs) and nutrients (digestive system) to body, and carbon dioxide from body to lungs Carries waste products from cells to kidneys Fight infection and heals wounds There are 4 components to blood: Plasma. Red blood cells. White blood cells Platelets

Plasma Plasma is the liquid portion of blood. Plasma is 92% water. Plasma carries nutrients, salts, hormones, enzymes, wastes, white blood cells, & red blood cells.

Red Blood Cells (RBC) Red blood cells carry oxygen & carbon dioxide throughout the body. Have hemoglobin which binds to oxygen and carries it in the RBC. RBC’s are made in bone marrow

White blood cells (WBC) White blood cells protect the body against infection. Most are created in bone marrow

Platelets Platelets are cell fragments that help clot blood.

The separation of blood Plasma Platelets White blood cells Red blood cells Whole Blood Sample Sample Placed in Centrifuge Blood Sample That Has Been Centrifuged

Cardiovascular Disease Atherosclerosis Atherosclerosis is caused by fatty deposits which build up on the inner walls of the arteries. The most common cause of heart attacks today Kills over 1 million Americans a year

Hypertension Aneurysm High blood pressure Damages blood vessels and makes the heart work harder. Can cause strokes & contribute to heart attacks. Aneurysm Weakened, bulging artery wall; can burst No symptoms!

Stroke Interruption of blood to the brain Caused by aneurysm, blood clot, or atherosclerosis Can lead to partial paralysis or death Risk Factors Age Gender Genetics High fat diet High blood pressure Smoking Stress Alcohol Obesity Inactivity