1. Respiratory System Gas exchange

2. W O R K T G E H
Why do we breathe? Think of all the reasons why we need a respiratory system.

3. Respiratory System Functions: Provides oxygen to the blood
Removes CO2 from the blood

4. Cells Many different types of cells are formed during embryonic
development.

5. Organization of the Body
Levels of Organization Eleven Organ System

6. Levels of Organization
Molecule
Cell
Tissue
Organ
Organ system
Organism

7. Homeostasis
The body maintains stable internal conditions which are relatively constant

8. Homeostasis & the Respiratory System
body = trillions of cells: needs FOOD (digestive) and AIR (respiratory)
Cellular Respiration: C6H12O6 = O2  CO2 + H2O + ATP
THEREFORE supply of O2 in blood CRITICAL for homeostasis
Without O2, cells cannot make energy
CO2 must also be managed so that this waste doesn’t accumulate to problematic levels.

9. Respiratory System Organs
Alveoli
Bronchi
Bronchioles
Diaphragm
Larynx
Lungs
Nose
Trachea

10. Structure
Bronchi/Bronchus
Bronchioles

12. Warning: terminology! “Respiration” is used several different ways:
Cellular respiration is the aerobic breakdown of glucose in the mitochondria to make ATP.
Respiratory systems are the organs in animals that exchange gases with the environment.
“Respiration” is an everyday term that is often used to mean “breathing.”

13. Moving air in and out
During inspiration (inhalation), the diaphragm muscle moves DOWN
During exhalation, these muscles relax. The diaphragm moves upwards.

14. Alveoli
The alveoli are thin- walled pockets which are the site of gas exchange.

15. Gas exchange
Air entering the lungs (alveoli) has more O2 & less CO2 than the blood that flows in the pulmonary capillaries
How do these differences in concentrations assist gas exchange?

16. Circulation and Gas Exchange
Gas exchange at the lungs moves oxygen into cells and carbon dioxide out (Diffusion) Clear connection between circulation and the respiratory system.

17. Oxygen transport Hemoglobin= iron in blood
Hemoglobin binds to O2 that diffuses into the blood stream.
Red blood cell transports oxygen to all body cells