Circulatory System
What Do These Two Systems Have In Common? (Think-Pair-Share) Subway System Circulatory System
Job of the Circulatory System Acts as a highway to carry oxygen and nutrients toward your cells while carrying wastes and carbon dioxide away from cells. Your heart pumps 4300 gallons of blood per day! THINK! - What parts make up your circulatory system? Heart Blood vessels (arteries, veins, capillaries) Blood
The Heart Your heart is located behind the sternum and is the size of your fist. THINK! – What muscle tissue makes up the heart? Cardiac The heart has 4 chambers: The two upper chambers are the atria. Two lower chambers are the ventricles. The septum is a thick muscle that separates the right and left sides of the heart so oxygen poor and oxygen rich blood do not mix. Valves are flaps of tissue that prevent the blood from flowing backwards Your Heart as 2 Pumps - http://www.kscience.co.uk/animations/heart.swf
Parts of the Heart Aorta Pulmonary Artery Vena Cava Pulmonary Veins (carries blood to body) Pulmonary Artery (carries blood from the heart to the lungs) Vena Cava (brings blood from body back to the heart) Pulmonary Veins Left Atrium Right Atrium Left Ventricle Valves Right Ventricle Septum
Blood Vessels of the Body Arteries carry blood “away” from the heart Veins carry blood “back” to the heart Capillaries the tiniest vessels where oxygen and nutrients can diffuse from bloodstream into cells Only 1 cell thick You can see them nourishing the white part of your eye
The Heart and Circulation The job of the heart is to circulate blood throughout the body The Heart is really 2 pumps working side by side: The right side pumps blood to the lungs to pick up oxygen. The left side pumps oxygenated blood to all tissues of the body. Check out this simple clip first http://www.kscience.co.uk/animations/blood_system.swf
Activity: Trace the Pathway of Blood During a Heart Beat 1. Oxygen poor blood enters the heart through the vena cava. 2. Blood is then pumped into the right atrium and then right ventricle. 3. Oxygen poor blood is pumped, exits the pulmonary artery and goes to the lungs. 4. Once it has oxygen, blood reenters the heart. 5. Blood is pumped into the left atrium and then left ventricle. 6. Oxygen rich blood is pumped out of the aorta to the body tissues.
Label and Color Code the Pathway of Blood THINK! – What sound does the heart make? LUB DUB LUB DUB As blood is pumped from atria to ventricles the “lub” sound is made ventricles to body, the “dub” sound is made.
Heart Disease Atherosclerosis Hypertension Build up of fat and cholesterol in arteries Leads to heart attack Heart Disease: United Streaming Hypertension High blood pressure Clogged arteries can cause high blood pressure Normal pressure is 120/80 THINK! – What do these numbers mean? First number – measures pressure when ventricles contract Second number – measures pressure when ventricles relax