1. Cardiorespiratory system

4. Cardiovascular SystemRespiratory System • Transportation of nutrients, gases, and waste • Protection from infection and blood loss • Maintenance of body temperature • Supply blood with oxygen • Removal of carbon dioxide

5. Cardiovascular system • BLOOD VESSELS “the roads, railway tracks, and airways of the body” • Arteries • Veins • Capillaries BLOOD VESSELS “the roads, railway tracks, and airways of the body” Arteries “freeway” – carry blood AWAY from the heart Veins – carry blood TOWARDS the heart Capillaries “side streets”– tiny, ‘hair-like’ blood vessels where gas exchange occurs

6. Cardiovascular system • Heart – pump of the body • About the size of your fist • Your heart is a muscle (remember involuntary cardiac muscle!) that contracts and relaxes automatically approximately 70 beats per minute at rest • The heart is divided into a right and left half – each are pumps and ensure there’s no mixing between oxygenated blood and deoxygenated blood • Each half of the heart is in charge of pumping blood through different blood vessel circuits

7. THE HEArt • 4 chambers of the heart • Atria – right/left • Ventricles – right/left • Valves – ensure blood flows in a one • direction • tricuspid, pulmonary, mitral (bicuspid), aortic • Veins – carry blood TOWARDS the heart • Superior Vena Cava • Inferior Vena Cava • Pulmonary Vein* • Arteries – carry blood AWAY from the heart • Pulmonary Artery* • Aorta • Septum – separates the left and right ventricles septum

8. Blood flow through the heart

9. Blood flow through the heart • Oxygenated blood enters the left atrium through the pulmonary veins* • The left atrium pumps the blood through the mitral valve into the left ventricle • The left ventricle contracts and pumps the blood through the aortic valve towards the body systems where the oxygen is delivered through the capillaries • The deoxygenated blood is transported back towards the heart through the veins. The superior and inferior vena cava both transport deoxygenated blood to the right atrium • The right atrium contracts and pumps the blood through the tricuspid valve • The right ventricle pumps the blood through the pulmonary valve to the pulmonary artery* which delivers the deoxygenated blood to the lungs where it become oxygenated blood through gas exchange in the capillaries • The pulmonary vein then transports the oxygenated blood to the left atrium where the cycle is continued (about 70 times per minute!) *????????

10. ACTIVITY TIME • Turn to page 36 in your PINK notebook • LABEL THE HEART • COLOUR THE OXYGENTATED HALF IN RED AND THE DEOXYGENTATED HALF IN BLUE • 2. Time-permitting: in groups of 3, create a song, skit, or comparison to explain the blood flow through the heart.