Circulatory and Respiratory System 1. Circulatory System – made up of three parts, the heart, blood vessels, and the blood. 2. Blood – a tissue that is made of liquid, cell parts, and two types of cells. Approximately 5 liters in the body. 3. Plasma – a liquid that makes up 55% of blood. 4. Platelets – cell fragments that help repair blood vessels that are solids that include blood cells and cell parts that make up 45% of blood. 5. Red Blood Cells (RBC’s) – Carry oxygen and carbon dioxide through the body. 6. Hemoglobin – protein in red blood cells that carry gases, oxygen and carbon dioxide attach to hemoglobin. 7. White Blood Cells (WBC’s) – cells that fight infection and protect the body from foreign particles. 8. Arteries – blood vessels that carry blood away from the heart. 9. Veins – blood vessels that carry blood back to the heart. 10. Capillaries – microscopic blood vessels that link arteries to veins. 11. Respiratory System – body system that brings oxygen into the body and removes carbon dioxide from the body. 12. Pharynx – air passes into the mouth and nose through the pharynx to the larynx and trachea. 13. Bronchi – the trachea branches into two tubes called bronchi. 14. Lungs – large sponge like organs in which oxygen and carbon dioxide are passed between the blood and the environment.