1. Respiratory System Notes
DJGYZ

2. Respiratory System Functions:
1. Brings oxygen (O2) into the body from the environment
2. Removes waste gases (CO2 and H2O) from the body
Breathing!!!

3. Respiration = Breathing
Breathing: bringing oxygen into the body and removing CO2 and H2O
Respiration: The breaking down of glucose molecules inside of cells using oxygen to produce energy (also called cellular respiration)

4. Upper Respiratory Tract
Nose
Nasal Cavity
Mouth
Pharynx (Throat)
Larynx (Voice Box)

5. Lower Respiratory Tract
Trachea (windpipe)
Bronchi
Lungs
-Bronchioles
-Alveoli

6. Lungs Major organs of the respiratory system Inside the lungs:
Alveoli: small sacs surrounded by capillaries (small blood vessels)
Site of gas exchange

7. Gas Exchange
In the alveoli the oxygen (O2) from the inhaled air passes into the blood, and carbon dioxide (CO2) and water (H2O) leave the blood and enter the alveoli

8. Gas Exchange

9. Pleura and Diaphragm
Pleura: layer of epithelial tissue that covers the outside of the lungs
Diaphragm: the muscle below the lungs that helps you breathe

10. Breathing: How its Done
Inhalation (breathing in): diaphragm contracts, increasing the volume in the chest cavity, which lowers the air pressure; the higher air pressure outside the body forces air into the lungs

11. Breathing: How its Done
Exhalation (breathing out): diaphragm relaxes, decreasing the volume in the chest cavity, which raises the air pressure; the higher air pressure inside the body forces air out of the lungs

12. Why do we breathe? We breathe so that we can get oxygen into our cells
Why do our cells need oxygen?
Cells use oxygen in a process called cellular respiration
Cellular Respiration:
Food + Oxygen = Energy (ATP) + CO2
CO2 is produced as a waste product in cellular respiration...it is removed from the body through the lungs!

13. Why is it dangerous to hold your breath too long?
Holding your breath stops oxygen from getting to the cells in all of your organs (especially your brain cells).
This stops the cells from producing enough energy to survive, which kills the cells!