1. Respiratory System
Chapter 37

2. Respiratory System
The exchange of O2 and CO2 between the body’s tissue, blood, and air.
Pharynx
Passageway for both air and food
Trachea
Windpipe. Epiglottis prevents other things from entering when you swallow.

3. Respiratory System Larynx Vocal chords
Elastic tissue that produce sounds when pulled tight and air passes through

4. Respiratory Anatomy

5. Respiratory System Cilia and Mucus
Mucus lines respiratory system and traps dust and smoke
Cilia sweeps trapped particles away from lungs

6. Respiratory System Air flows through nasal passage
Air is moistened and filtered. Why?
Filtered: to protect lungs
Moistened:
gasses diffuse through water
moisture maintains cell membranes where gasses pass through

7. Bronchi Trachea branches into two Bronchi Each Bronchi leads to a lung
Branch then divides into more smaller branches - Bronchioles
Bronchioles end up as ALVEOLI

8. Alveoli Where the gas exchange occur
CO2 exits capillaries and into aveoli
We expel (exhale) CO2
O2 inhaled into alveoli
O2 enters capillaries

10. Alveoli Gas exchange occurs across epithelium of alveoli
Millions of alveoli = very high surface area

11. Red Blood Cells Hemoglobin Iron containing Protein
O2 binds to hemoglobin
Only found in Red Blood Cells
Increasing the amount of O2 in the blood

12. Breathing
Diaphragm
Contracts when you breathe in. Chest volume increases
Relaxes when you exhale. Chest volume decreases

14. Breathing is automatic
Medulla Oblongata
Breathing control center
Detects level of CO2
If CO2 levels are high, Diaphragm will contract