1. Gas Exchange
Lizzie Cymanski

2. Functions Acquisition of oxygen Distribution of gases
Removal of carbon dioxide

3. Importance Oxygen is needed for cellular respiration
The body needs to get rid of carbon dioxide, the product of cellular respiration

4. Cellular Respiration vs. Respiration
Cellular Respiration -- the use of oxygen and production of carbon dioxide at a cellular level
also called internal respiration
Respiration -- the uptake of oxygen from the environment and the disposal of carbon dioxide at the body system level
also called external respiration

5. Respiratory system needs:
large respiratory surface (lungs, gills)
a method for ventilating respiratory surface
a pump and circulatory system to distribute gases

6. Bacteria
In bacteria and other very small organisms, cells are in always in contact with the environment
Gas exchange happens easily

7. Respiratory Surfaces The first respiratory surface was skin
doesn’t work for larger animals
Most amphibians still use skin for 100% of their gas exchange
Fish, reptiles, humans get some respiratory gases from skin

8. Evolution
As animals grew larger, their body’s surface area wasn’t large enough for gas exchange through skin
Aquatic animals developed gills, terrestrial animals developed lungs

9. Lungs
Humans have two lungs -- the left divided into two lobes, the right, three
Two zones -- the conducting zone and the respiratory zone
Protected by the rib cage

10. Conducting Zone
Trachea -- connects the pharynx to the lungs, allows the passage of air
Trachea divides into two bronchi which divides into bronchioles which divides into terminal bronchioles
No gas exchange with blood
Warms, cleans and humidifies air
Reinforced with cartilage to keep airways open

12. Respiratory Zone alveolar ducts -- the tiny ends of the airways
alveoli -- form at the end of alveolar ducts, sac-like structures, site of gas exchange
outube.com/watch?v=Aw9OJL TlClQ&feature=fvst

13. Pleural Cavity Lungs covered in visceral pleural membrane
Lungs lined in parietal pleural membrane
The pleural cavity is the space between the two membranes
The cavity is filled with water to hold the two membranes together

14. Interesting Facts The lungs: contain 1500 miles of airways
300 to 500 million alveoli
total surface area of 70 sq. miles -- about the size of one side of a tennis court
If all the capillaries were unwound, they would be 620 miles long

16. Circulatory System
The circulatory delivers the oxygen to cells all over the body and then carries away carbon dioxide
Most oxygen is bound to molecules of hemoglobin inside red blood cells

17. Hemoglobin
A protein made of four polypeptide bonds and four organic compounds called heme groups
At the center of each heme group is an atom of iron
The iron molecule can bond to a molecule of oxygen
Each hemoglobin can carry four oxygens

18. (De)Oxyhemoglobin
Oxyhemoglobin – hemoglobin that is full of oxygen, a bright red color
Deoxyhemoglobin – hemoglobin that has released its oxygen, a dark red that appears blue under tissue

19. History of Hemoglobin Hemoglobin is an ancient protein
Not only used in vertebrates but also in annelids, mollusks, echinoderms, flatworms, and even some protists
Other invertebrates use hemocyanin which has a base of copper instead of iron

20. Emphysema
One of the main forms of Chronic Obstructive Pulmonary Disease (COPD)
The destruction of the lungs over a long period of time
Most common cause is smoking, also caused by exposure to pollution
Cannot be cured but can be treated

21. Emphysema Symptoms Cough with mucus Shortness of breath Fatigue
Wheezing
Frequent respiratory infections

22. Tuberculosis Caused by the bacteria Mycobacterium tuberculosis
Very contagious
Can be cured but takes very long time
If not treated properly, spreads to other organs

23. TB Symptoms Cough Coughing up blood Excessive Sweating Fatigue Fever
Weight loss

24. Cystic Fibrosis Inherited disease
Causes thick, sticky mucus to build up in lungs and digestive tract
May also affect sweat glands and male reproductive system
Most commonly affects Caucasians
Only live to mid-30’s

25. Cystic Fibrosis Symptoms
Salty-tasting skin
Frequent lung infections
Wheezing and shortness of breath
Delayed growth
Problems with bowel movement

26. http://cwx.prenhall.com/bookbind/pubbooks/martini10/c hapter24/custom2/deluxe-content.html
body/systems/respiratory/lung.htm