1. The path of an oxygen as it enters your mouth, travels to your lungs and through the bloodstream to the body cells for respiration By Katherine Martin

2. Entering the body = air

3. Entering the body Every day we breathe in a mixture of gases called air, which includes oxygen (21%) and carbon dioxide (0.04%). Every time we breathe we inhale oxygen and remove carbon dioxide from our body. We need oxygen so we can break down the food we eat to absorb and use the energy, this is a chemical reaction called respiration.

4. Entering the body Trachea Mouth Bronchi Lungs = air

5. Entering the body When we breathe, the air travels down our trachea (also known as the windpipe) to the lungs.

6. Inside the Lungs Trachea Alveoli Bronchi Bronchioles = air Lungs

7. Inside the lungs At the end of trachea it divides into 2 smaller tubes called bronchi. The air then travels to even smaller tubes called bronchioles, and then to air sacs called alveoli.

8. Entering the Bloodstream Alveoli Sacs Pulmonary Artery Alveoli Bronchiole Pulmonary Vein = air

9. Entering the Bloodstream = capillary = blood cell = alveoli = air

10. Entering the Bloodstream As we breathe the alveoli are filled with air which stretches them, making them very thin. This is when oxygen can pass through the lung tissue into the bloodstream (capillaries). Once in the blood stream the oxygen locks onto the blood cells making it oxygenated (turning red).

11. Through the Heart Left Atrium To the Body To the Lungs To the Lungs From the Lungs From the Lungs Left Ventricle Right Atrium Valve Vena Cava Right Ventricle = blood cell

12. Entering the body Then the blood cells travel through the bloodstream to the left side of the heart and then is pumped to the rest of the body.

13. Through the body Tissue Bloodstream (Capillary) = oxygen = carbon dioxide

14. Entering the body Once the blood cells reach the part of body needed, the oxygen unlocks from the blood cells making it deoxygenated (turning blue); and passes through the bloodstream to the body part need to cause the chemical reaction to use the energy from food. As they oxygen does this carbon dioxide enters the blood stream and takes the opposite journey to be breathed out.

15. Bibliography