The Respiratory System

1. The Respiratory System

2. Major Functions of the Respiratory System • supplies the blood with oxygen which is then delivered to all of the bodies trillions of cells • Removes Carbon Dioxide from the blood and expels it from the body

3. Why do we need Oxygen? • Oxygen (O2) is an essential gas in cellular respiration. This process generates ATP (energy molecules) in the mitochondria of all cells. • The primary waste product generated by cellular respiration is carbon dioxide (CO2)

4. The air we breathe

5. Respiratory System Organs: Mouth, Nose, and Larynx • When air enters your mouth/nose, mucus aids in humidifying and warming the air before it enters your lungs. • It passes over your larynx, or voice box, which has vocal folds able to generate sound. The larynx also protects the trachea.

6. Challenge Question! • When you sneeze particles fly from your nose and mouth at nearly 100 mph! What is the physiologic reason why one would need to sneeze?

7. Respiratory System Organs: Pharynx and the Epiglottis When you eat, a flap of connective tissue called the epiglottis prevents food from entering the trachea. In the back of the throat, the place where the nasal cavity and the oral cavity meet is called the pharynx.

8. Respiratory System Organs: The Trachea • The trachea, or windpipe, is a tube made of cartilage rings that branches into 2 bronchi. It is lined with cilia and mucus designed to filter harmful particles from the air we breathe.

9. Respiratory System Organs: Bronchi and Bronchioles • The trachea opens into 2 bronchi and then continues to branch into smaller and smaller tubes called bronchioles. Gas exchange does NOT take place here…

10. Bronchial Histology

11. Bronchial Epithelium scanning electron micrograph (SEM) of bronchial epithelium (the mucus membrane lining the major airways of the lung). Clumps of hair-like cilia protrude from the tops of specialized columnar epithelial cells. Rhythmic movements of the cilia serve to move bacteria and other particles away from alveoli and towards the throat, where they are expelled or swallowed.

12. Lung Tissue Histology The alveoli are composed of a single layer of squamous epithelium. Between the alveoli you may see a thin layer of areolar connective tissue and numerous capillaries also lined with simple squamous epithelium.

13. Respiratory System Organs: Alveoli • The bronchioles terminate in tiny sac-like structures called “alveoli,” O2 and CO2 are exchanged here in microscopic blood vessels called capillaries.

14. Capillary Carbon Dioxide is dropped off Wall of the air sac Oxygen is picked up Red Blood Cell Inside and Alveoli • The average individual has approximately 700 million functional alveoli. MB

15. Inside and Alveoli (cont) C A B • Can you Identify these structures?

16. Inside and Alveoli (cont) C A • What tissue has been removed in this image? What do the black lines represent? B

17. Cool pictures In Summary… JH

18. Did you Know?... The surface area of the lungs is roughly the same size as a tennis court!

19. Did You Know?... A “Yawn” occurs when a person’s blood contains elevated levels of carbon dioxide. the influx of oxygen provided by the yawn helps re-establish homeostasis.

20. Respiratory System Organs: The Pleura • The pleura, or pleural cavity, is a fluid filled double membrane that surrounds the lungs. It effectively creates a closed space (like a balloon) for the lungs to operate.

21. The Lobes of the Lungs

22. Did you know? • Chemicals in cigarette smoke damage alveoli. Normal lung Smokers lung

23. The Circulatory System and the Respiratory System • The primary vehicle for gas exchange is the red blood cell. These cells have a protein called hemoglobin, which attach to and release respiratory gases.

24. Hemoglobin: A Closer Look

25. The Circulatory System and the Respiratory System • Blood is delivered to the lungs via the heart in a process called “pulmonary circulation.” Oxygenated blood is then transported back to the heart, and pumped to all of the bodies tissues.

27. Respiratory System Organs: The Diaphragm • The diaphragm is a large muscle that separates the abdominal and thoracic cavities. When you inhale, it moves downward and your ribcage expands. When you exhale it returns to its normal position and air is expelled from the lungs.

29. Using a Spirometer: Factors affecting volumes Several factors affect lung volumes; some can be controlled and some cannot. Lung volumes can be measured using the following terms: Average forced lung capacity: Male: 4.6 LitersFemale 3.5 Liters

30. Chronic Obstructive Pulmonary Disease Emphysema is a lung disease involving damage to the air sacs (alveoli).There is progressive destruction of alveoli and the surrounding tissue that supports the alveoli.

31. Non-Respiratory Functions Exhalation provides a route for water loss and heat elimination. Helps regulate blood pH Enables speech Defends against inhaled foreign material/pathogens. Smell

32. Key Respiratory EnzymesCarbonic Anhydrase Manufactured in cells throughout the body, this enzyme catalyzes the synthesis of carbonic acid from CO2 and water. This is crucial in all body tissues, as CO2 insoluble in water. In the lungs, a related enzyme facilitates the decomposition of carbonic acid into water and carbon dioxide for excretion.

33. Key Respiratory EnzymesACE Angiotensin-converting enzyme (ACE) is enzyme is part of a complex, multiple component feedback system involving the liver, heart, lungs, and kidneys. ACE has several effects on the lungs and converts the hormone angiotensin I to angiotensin II (from the liver), causing vasoconstriction, therefore helping maintain hydrostatic homeostasis.

35. Bronchitis

36. Asthma

37. Fun Facts! • At rest, the body takes in and breathes out about 10 liters of air each minute. • The right lung is slightly larger than the left. • The capillaries in the lungs would extend 1,600 kilometers if placed end to end. • We lose half a liter of water a day through breathing. This is the water vapor we see when we breathe onto glass. • A person at rest usually breathes between 12 and 15 times a minute. • The breathing rate is faster in children and women than in men.

38. Did you know…. David Blaine set a new world record for breath-holding on April 30, 2008, at 17 minutes, 4.4 seconds, during a live telecast of The Oprah Winfrey Show.

39. Pop Quiz! • Can you identify structures 1-6?

40. Pop Quiz #2 (easy)Fill in the Blank Burning fuel (food) requires __________ All living things carry out _________. 2 waste products generated by cellular respiration include water and _______. Small blood vessels where gas exchange occurs: ________ Cilia and mucus help moisten and _______ the air we breathe. Another word for “windpipe” __________ Another word for “voice box” _________ Air sacs in your lung where gas exchange takes place: _________ The respiratory system works most closely with this body system: __________ ___________. This tiny structure prevents choking when you eat. __________

41. Pop Quiz #3 (harder)Fill in the Blank The formula for cellular respiration is: ___________________________________ ________ protrude from the tops of specialized columnar epithelial cells in bronchioles. _______ is the functional component within hemoglobin protein molecules. Expansion of the ribcage generates _________ __________, forcing air into the lungs. The alveoli are composed of a single layer of __________ _________. Mast cells generate __________. ___________ __________ protects the larynx. ___________ __________ delivers blood to and from the lungs from the heart. Smoking can cause Chronic Obstructive Pulmonary Disease, or ____________. The atmosphere is composed of 79% diatomic __________ and 20% diatomic __________. The _________ _________ is a fluid filled double membrane that surrounds the lungs.

42. That’s All Folks!