1. Intro to the Human Respiratory System

2. Brainstorm
With a small group of students, answer the questions on your handout.
You will have 5-10 minutes to think about these questions and answer them.

3. I. Purpose of Gas Exchange
Obtain oxygen for cellular respiration (to make ATP, a form of energy)
Get rid of carbon dioxide, a waste product of cellular respiration

5. What is the function of mucus and cilia?
Unit 2, Topic 6 - Respiratory System
What is the function of mucus and cilia?

6. These parts contain mucus, but no cilia:
Bronchioles Alveoli—respiratory surface, where gas exchange takes place

7. Alveoli are surrounded by capillaries
Alveoli (plural) = small balloon-like structures) at the end of the bronchioles
One cell layer thick and HOLLOW
Surrounded by capillaries
Allows for gas exchange between air and blood
Lungs contain about 300 million alveoli
70 square meters (40X the Surface Area of skin)

8. Diffusion takes place between the alveoli and the blood vessels

9. Diffusion and the Role of Blood:
A. Blood picks up oxygen in the lungs and drops it off at body cells.
B. Blood picks up carbon dioxide at from body cells and drops it off in the lungs.

11. Diseases of Membrane Transport and the Respiratory System
Unit 2, Topic 6 - Respiratory System
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Diseases of Membrane Transport and the Respiratory System

12. Cystic Fibrosis - youtube
Genetic disorder common in Caucasians
recessive gene
Sodium pump in cells of the lungs don’t work (example of active transport!)
Sodium builds up, creating a hypertonic cell
Water osmoses into the cells from the mucus
Mucus becomes thick and difficult to move
What happens as a result?

13. Cystic Fibrosis – 9 second animation

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

16. Asthma Severe allergic reaction
Bronchioles go into spasms, constricting the air passages

17. Pneumonia Alveoli become filled with fluid Caused by an infection
Prevents exchange of gases
Caused by an infection

19. Smoking-related disorders
Causes cilia to stop moving (for 20 minutes)
Increases amount of mucus in the air passages
Decreases the amount of oxygen carried by blood

20. Smoking Hot Facts (from NIH)
2004: 29.2% of the U.S. population 12 and older(70.3 million)used tobacco
Cigarettes contain formaldehyde, cyanide, carbon monoxide, ammonia, and nicotine
Carbon Monoxide binds to hemoglobin (oxygen has to compete with it)
Nicotine stimulates release of epinephrine-- glucose raised in blood, gives “kick”
Quitting is difficult: withdrawal includes impaired language comprehension, increased irritability

21. Smoking Slides – Web MD
Smoking affects how your appearance and odor Age spots are blotches of darker skin color that are common on the face and hands. While anyone can develop these spots from spending too much time in the sun, research suggests smokers are more susceptible.
In this image, the twin on the right spent decades smoking and sunbathing, while her sister did not.  

22. Unit 2, Topic 6 - Respiratory System
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Emphysema - youtube
Primarily caused by smoking
Lungs lose elasticity (difficult to exhale)
Alveoli become damaged
Lose surface area for gas exchange
Why is this associated with heart problems?

23. Unit 2, Topic 6 - Respiratory System
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Unit 2, Topic 6 - Respiratory System

24. Bronchitis
Linings of the bronchial tubes become irritated and swollen.
May clog with mucus
Severe coughing and difficulty breathing
Caused by an infection or by pollutants

25. Lung Cancer
Tumors form in the lungs

27. What chemicals are in cigarette smoke? What do these chemicals do?
What are carcinogens? Are there carcinogens in cigarette smoke? Name them.
How much does a smoker spend per year on cigarettes?
How are lungs affected by cigarettes?
How are infants born to smoking mothers affected?
What is second hand smoke?
What is third hand smoke?
What diseases are smokers more likely to have? Why?
Are cigarettes addictive? What chemicals make them habit forming?
What happens to the body when you smoke?

28. Animation: O2 from Blood to Tissues
Student Misconceptions and Concerns
1. Many students still struggle with the concept of diffusion as the main mechanism of gas transport. Before discussing gas transport, ask your class to explain why oxygen moves out of the blood in body tissues, but into the blood in the lungs. Why don’t these processes proceed in the opposite direction?
2. Many students struggle with fundamental aspects of fetal circulation and respiration. Students might assume that the mother’s blood flows through the umbilical cord into the fetus. Students might also expect that the fetus is somehow breathing air. Nobody likes to be embarrassed by ignorance, so gauging these and many other misconceptions can be a challenge. To better understand your students’ background knowledge consider giving a short quiz on fundamental points before lecturing on the subject.
Teaching Tips
Figure is an especially helpful depiction of the movements of gases in the human respiratory system. The figure includes all of the main sites where oxygen is consumed, the alveoli where gas exchange occurs in the lungs, and the separate movement of oxygenated and deoxygenated blood through the heart.
Animation: O2 from Blood to Tissues
Right click on animation / Click play
© 2012 Pearson Education, Inc. 28

29. Animation: O2 from Lungs to Blood
Student Misconceptions and Concerns
1. Many students still struggle with the concept of diffusion as the main mechanism of gas transport. Before discussing gas transport, ask your class to explain why oxygen moves out of the blood in body tissues, but into the blood in the lungs. Why don’t these processes proceed in the opposite direction?
2. Many students struggle with fundamental aspects of fetal circulation and respiration. Students might assume that the mother’s blood flows through the umbilical cord into the fetus. Students might also expect that the fetus is somehow breathing air. Nobody likes to be embarrassed by ignorance, so gauging these and many other misconceptions can be a challenge. To better understand your students’ background knowledge consider giving a short quiz on fundamental points before lecturing on the subject.
Teaching Tips
Figure is an especially helpful depiction of the movements of gases in the human respiratory system. The figure includes all of the main sites where oxygen is consumed, the alveoli where gas exchange occurs in the lungs, and the separate movement of oxygenated and deoxygenated blood through the heart.
Animation: O2 from Lungs to Blood
Right click on animation / Click play
© 2012 Pearson Education, Inc. 29

30. Alveolar capillaries of lung Tissue cells throughout the body
Figure 22.10
CO2 in exhaled air
O2 in inhaled air
Alveolar epithelial cells
Air spaces
CO2 O2
CO2 O2
Alveolar capillaries of lung
CO2-rich, O2-poor blood
O2-rich, CO2-poor blood
Figure Gas transport and exchange in the body
Tissue capillaries
Heart
CO2 O2
CO2
Interstitial fluid O2
Tissue cells throughout the body 30

31. Alveolar capillaries of lung
Figure 22.10_1 O2
CO2
Alveolar capillaries of lung
CO2-rich, O2-poor blood
O2-rich, CO2-poor blood
Figure 22.10_1 Gas transport and exchange in the body (detail)
Tissue capillaries
Heart
CO2 O2 31

32. Unit 2, Topic 6 - Respiratory System
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Surfactant
Surface tension pulls alveoli shut – surfactant prevents this by lessening surface tension
Appears at 33 weeks gestation (normal length is weeks)
Before 28 weeks premature ½ suffer from respiratory distress and artifical surfactant can be delivered

33. Unit 2, Topic 6 - Respiratory System
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Breathing Air vs. Water
Air
210 mL O2/L air
Lighter
Dry! – It needs to be dissolved in water
May lose water through evaporation
How can we fix that?
Water
5-10 mL O2/L water
Heavier
Already dissolved in water (like your cells)

34. Figure 42.21 Countercurrent exchange
Unit 2, Topic 6 - Respiratory System
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Figure 22.3, Pg 456