1. The Circulatory System
Video (6min 14sec):

2. The Circulatory System
Composed of the blood, heart and blood vessels (arteries, veins and capillaries)
It is responsible for transporting substances throughout the body
It carries oxygen and nutrients to the cells and carbon dioxide and wastes away from cells

3. Blood
Red blood cells contain a protein called hemoglobin which binds oxygen
Hemoglobin contains iron, and when bound to oxygen makes the cells appear red

4. Blood
White blood cells are part of the body’s immune system and are used to fight infection

5. The Heart
The heart is the muscular organ that pumps blood to the cells and then back to the heart
The heart contains four chambers – two upper chambers and two lower chambers
The right side of the heart pumps blood to the lungs, the left side pumps blood to the rest of the body

7. Blood Vessels
Make up the network of tubes that carry blood throughout the body
Arteries
carry blood away from the heart
Veins
carry blood to the heart

8. Blood Vessels Capillaries Smallest blood vessel
Link veins are arteries together
Point of gas exchange

9. Your turn Explain the function of the circulatory system.
How does the circulatory system work together with the respiratory system
An athlete measures how fast his heart is beating before and immediately after a race. What is likely to observe and why?
Trace the path of blood, starting and finishing in the lungs.