1. Unit 2, Topic 6 - Respiratory System Topic 1: Gas Exchange
Unit 3: Body Systems
Topic 1: Gas Exchange

2. Levels of Organization in Biology
Small systems to Big systems

3. This Section deals with
Biochemistry and Macromolecules

4. This Section deals with
Anatomy

5. This Section deals with Ecology

7. Gas Exchange
Why?
Aerobic Cellular Respiration
C6H12O6 + 6O2  6 CO2 + 6H2O
Every cell of an organism requires O2 (reactant) for use in Aerobic Cellular Respiration
Every cell of an organism produces CO2 (product)
Composition of Air

8. Gas exchange in single celled organisms
Obj 1
Gas exchange in single celled organisms
Exchange between organism and environment
Occurs through the cell membrane
Small non-polar O2 and CO2 are permeable

9. Gas Exchange in Multicellular Organisms
Unit 2, Topic 6 - Respiratory System
OBJ 1
Gas Exchange in Multicellular Organisms
The cells of small multicellular organisms exchange gases with out the aid of a circulatory system

10. Gas Exchange in Multicellular Organisms
Unit 2, Topic 6 - Respiratory System
OBJ 1
Gas Exchange in Multicellular Organisms
Larger multicellular organisms require a circulatory system to move gases to each and every cell

11. Unit 2, Topic 6 - Respiratory System
Gas Exchange in Fish

12. Human Respiratory System
Unit 2, Topic 6 - Respiratory System
OBJ 2
Your Goal: Describe the path of air in and out of the lungs using anatomical terms and describing the relative concentrations of O2 and CO2
Nasal and oral cavity
Start with Humans (G block); Start with Alveoli (E block)
Capillary – tiny blood vessel

13. Cell Specialization - Example
Unit 2, Topic 6 - Respiratory System
Cells lining the trachea
Goblet cells – secretes mucus
Epithelial cell – ciliated cells, cilia move mucus layer towards pharynx, removing inhaled particles from the air way

14. Unit 2, Topic 6 - Respiratory System
Alveoli
Unit 2, Topic 6 - Respiratory System
OBJ 3
Functional unit of the lung. About 480 million per lung.
Location of gas exchange.
Surface Area!

15. Unit 2, Topic 6 - Respiratory System
OBJ 22
Unit 2, Topic 6 - Respiratory System

16. Unit 2, Topic 6 - Respiratory System
OBJ 3
Surfactant
Secretions that keep the alveoli open
Counteracts the cohesive properties of water
Start here with C-block

17. Unit 2, Topic 6 - Respiratory System
OBJ 4
Negative Pressure Breathing
Diaphragm – thin muscle separating the chest cavity from the abdominal cavity
Smaller chest cavity
Higher air pressure
Air forced out of lungs
Larger chest cavity
Lower air pressure
Air flows into lungs

18. Smoking-related disorders
Unit 2, Topic 6 - Respiratory System
OBJ 5
Smoking-related disorders
Smoking:
Causes cilia to stop moving (for ~20 minutes)
Increases amount of mucus in the air passages
Kills macrophages (immune cells) in respiratory tract
Increased exposure to cold and flu viruses
Decreases the amount of oxygen carried by blood

19. Unit 2, Topic 6 - Respiratory System
OBJ 5
Emphysema
Primarily caused by smoking
Lungs lose elasticity (difficult to exhale)
Alveoli become damaged
Lose surface area for gas exchange

20. Unit 2, Topic 6 - Respiratory System
OBJ 5
Unit 2, Topic 6 - Respiratory System

21. Unit 2, Topic 6 - Respiratory System
Lung Cancer
OBJ 5
20 carcinogens found in cigarette smoke have been directly linked to lung cancers (Hetch, 1999)
Smoking causes 1 in 3 of all cancer deaths in the USA. (ALA)
Tumors form in the lungs

22. Unit 2, Topic 6 - Respiratory System
Cystic Fibrosis
Unit 2, Topic 6 - Respiratory System
Optional OBJ 6
Genetic disorder common in Caucasians
Chloride pumps in cells of the trachea don’t work (what kind of transport?)
Cl- cannot leave the cell
Na+ uptake into the cell is increased
What happens as a result?
Leads to a hypertonic cytoplasm, water flows into the cell

23. Unit 2, Topic 6 - Respiratory System
OBJ 6
Cystic Fibrosis
CFTR Protein

24. Unit 2, Topic 6 - Respiratory System
OBJ 6
Unit 2, Topic 6 - Respiratory System

25. Unit 2, Topic 6 - Respiratory System
Other diseases
Bronchitis
Bronchial tube lining becomes irritated and swollen
May clog with mucus
Severe coughing and difficulty breathing
Caused by an infection or by pollutants

26. Unit 2, Topic 6 - Respiratory System
Other diseases
Asthma
Severe allergic reaction
Bronchioles go into spasms, constricting the air passages

27. Unit 2, Topic 6 - Respiratory System
Other diseases
Pneumonia
Alveoli become filled with fluid
Prevents exchange of gases
Caused by an infection