Intro to the Human Respiratory System

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.

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

What is the function of mucus and cilia?

These parts contain mucus, but no cilia:

Bronchioles

Alveoli—respiratory surface, where gas exchange takes place

Alveoli are surrounded by capillaries

Diffusion takes place between the alveoli and the blood vessels

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.

Diseases of Membrane Transport and the Respiratory System

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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?

Cystic Fibrosis – 9 second animation

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

Pneumonia Alveoli become filled with fluid◦ Prevents exchange of

gases

Caused by an infection

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

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

Smoking Slides – Web MDSmoking 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.  

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 withheart problems?

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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

Lung Cancer Tumors form in the lungs

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?

© 2012 Pearson Education, Inc.

Animation: O2 from Blood to TissuesRight click on animation / Click play

© 2012 Pearson Education, Inc.

Animation: O2 from Lungs to BloodRight click on animation / Click play

Figure 22.10CO2 in exhaled air

Alveolarepithelial

cells

O2 in inhaled air

Air spaces

Alveolarcapillaries

of lung

CO2 O2

O2

CO 2

CO2-rich,

O2-poor

blood

O2-rich,

CO2-poor

blood

HeartTissue

capillaries

O2C

O2

Interstitialfluid

Tissue cellsthroughout the body

CO2 O2

Figure 22.10_1

Alveolarcapillaries

of lung

O2

CO 2

CO2-rich,

O2-poor

blood

O2-rich,

CO2-poor

blood

HeartTissue

capillaries

O2

CO

2

Surfactant

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Breathing Air vs. WaterAir

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)

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Figure 42.21 Countercurrent exchange OBJ 25

Figure 22.3, Pg 456