1. Chapter 47 Circulatory and Respiratory Systems

2. Electrocardiogram

3. Lymphatic System

4. Structure of the Human Heart

5. A Closer Look at Blood Vessels

6. Systemic Circulation

7. Circulation Pathway in the Human Body

8. Circulatory Loops in the Human Body

9. Composition of Blood

10. Clotting Cascade

11. Blood Types

12. Mammalian Lung Structure

13. Respiratory System in the Human Body

14. Overview of Respiration

15. Your heart's job is to pump blood around your body. Its muscles contract and squeeze out blood. The left-hand side pumps blood from the lungs to the rest of your body. The right-hand side pumps stale blood from your body back to your lungs for a fresh supply of oxygen.

16. Artery Vein

17. Immune System Response Time

18. Respiratory System Your breathing parts

20. You usually cannot see the air you breathe out. But on cold days the air you exhale is visible. This is because your breath contains water vapor, as well as carbon dioxide. As the water vapor meets cold air, it condenses and turns into tiny droplets of liquid water which look like white puffs of steam.

21. When you breathe in your chest muscles pull your ribs up and out. Your diaphragm, the muscle under your chest, moves down. Your chest expands and your lungs fill with air. When you breathe out, the muscles relax. Your ribs move down, and your diaphragm moves up to squeeze air out.

24. Inflammatory Response

25. Events of the Immune Response