5/6

1. 5/6 • Please have your packet out. • Review respiratory packet/system • Power point review • Maybe discovery video

2. Overview of entire system • http://www.youtube.com/watch?v=9fxm85Fy4sQ • Crash course

3. Organs of the Respiratory system • Nose • Pharynx • Larynx • Trachea • Bronchi • Lungs – alveoli Figure 13.1

4. Function of the Respiratory System • Oversees gas exchanges between the blood and external environment • Exchange of gasses takes place within the lungs in the alveoli • Passageways to the lungs purify, warm, and humidify the incoming air

5. The Nose • The only externally visible part of the respiratory system • Air enters the nose through the external nares (nostrils) • The interior of the nose consists of a nasal cavity divided by a nasal septum

6. Upper Respiratory Tract Figure 13.2

7. Anatomy of the Nasal Cavity • Olfactory (smell) receptors are located in the mucosa on the superior surface • The rest of the cavity is lined with respiratory mucosa • Moistens air • Traps incoming foreign particles

8. Anatomy of the Nasal Cavity • The nasal cavity is separated from the oral cavity by the palate • Anterior hard palate (bone) • Posterior soft palate (muscle)

9. Paranasal Sinuses • Cavities within bones surrounding the nasal cavity • Frontal bone • Sphenoid bone • Ethmoid bone • Maxillary bone

10. ParanasalSinuses (reviewed in skeletal) • Function of the sinuses • Lighten the skull • Act as resonance chambers for speech • Produce mucus that drains into the nasal cavity

11. Pharynx (Throat) • Muscular passage from nasal cavity to larynx • The upper and middle pharynx are common passageways for air and food

12. Larynx (Voice Box) • Routes air and food into proper channels • Plays a role in speech • Made of eight rigid hyaline cartilages and a spoon-shaped flap of elastic cartilage (epiglottis)

13. Structures of the Larynx • Thyroid cartilage • Largest hyaline cartilage • Protrudes anteriorly (Adam’s apple) • Epiglottis • Superior opening of the larynx • Routes food to the larynx and air toward the trachea

14. Structures of the Larynx • Vocal cords (vocal folds) • Vibrate with expelled air to create sound (speech) • Glottis – opening between vocal cords

15. What is laryngitis? • Laryngitis is an inflammation of the voice box, or larynx ("LAIR-inks")., that causes your voice to become raspy or hoarse. • Laryngitis can be short-term or long-lasting (chronic). Most of the time, it comes on quickly and lasts no more than 2 weeks.

16. What causes laryngitis? • Colds or flu. This is the most common cause. • Acid reflux, also known as gastroesophageal reflux disease (GERD). This type of laryngitis is also called reflux laryngitis. • Overuse of your voice, such as cheering at a sports event. • Irritation, such as from allergies or smoke. • Some hoarseness may occur naturally with age as your vocal cords loosen and grow thinner.

17. Trachea (Windpipe) • Connects larynx with bronchi • Lined with ciliated mucosa which beat continuously in the opposite direction of incoming air to expel mucus loaded with debris away from lungs • Walls are reinforced with C-shaped hyaline cartilage

18. Tracheotomy! • consists of making an incision on the anterior aspect of the neck and opening a direct airway through an incision in the trachea. The resulting opening can serve as a site for a tracheostomy tube to be inserted; this tube allows a person to breathe without the use of his or her nose or mouth. • http://www.youtube.com/watch?v=d_5eKkwnIRs • http://www.youtube.com/watch?v=SloXwGG2n-Q&feature=related

19. NEWS!!! Friday, January 20th, 2012 • Synthetic Windpipe Transplant Boost For Tissue Engineering • Surgeons in Sweden replaced an American patient’s cancerous windpipe with a scaffold built from nanofibers and seeded with the patient's stem cells. Lead surgeon Dr. Paolo Macchiarini discusses the procedure and the benefits of tissue-engineered synthetic organs

20. Bronchi • Formed by division of the trachea • Bronchi subdivide into smaller and smaller branches

21. Lungs • Occupy most of the thoracic cavity • Apex is near the clavicle (superior portion) • Base rests on the diaphragm (inferior portion)

22. Each lung is divided into lobes by fissures • Left lung – two lobes • Right lung – three lobes

23. Lungs Figure 13.4b

24. Coverings of the Lungs • Pulmonary (visceral) pleura covers the lung surface • Parietal pleura lines the walls of the thoracic cavity • Pleural fluid fills the area between layers of pleura… WHY?

25. Bronchioles • Smallest branches of the bronchi which end in alveoli Figure 13.5a

26. Alveoli • Gas exchange takes place within the alveoli in the respiratory membrane • Pulmonary capillaries cover external surfaces of alveoli

27. Capillaries Alveoli

28. http://www.sciencefriday.com/program/archives/201006252 • Scientists building a real lung!

29. Gas Exchange • Gas crosses the respiratory membrane by diffusion • Oxygen enters the blood • Carbon dioxide enters the alveoli

30. Respiratory Membrane (Air-Blood Barrier) Figure 13.6

31. WHY do we need gas exchange? • Cellular respiration! Or the conversion of “food” to ATP. • Oxygen is the final electron acceptor. This is important b/c you do not want electrons zipping around your body possibly running into DNA and damaging it • Carbon Dioxide is a byproduct of the breakdown of “food” which contains a lot of carbon. We need to get rid of it b/c if we do not it turns to carbonic acid and decreased the pH which can kill cells!

32. Events of Respiration • External respiration – gas exchange between pulmonary blood and alveoli • Respiratory gas transport – transport of oxygen and carbon dioxide via the bloodstream • Internal respiration – gas exchange between blood and tissue cells in systemic capillaries

33. External Respiration • Oxygen movement into the blood • The alveoli always has more oxygen than the blood • Oxygen moves by diffusion towards the area of lower concentration • Pulmonary capillary blood gains oxygen

34. External Respiration • Carbon dioxide movement out of the blood • Blood returning from tissues has higher concentrations of carbon dioxide than air in the alveoli • Pulmonary capillary blood gives up carbon dioxide • Blood leaving the lungs is oxygen-rich and carbon dioxide-poor

35. Gas Transport in the Blood • Oxygen transport in the blood • Inside red blood cells attached to hemoglobin (oxyhemoglobin [HbO2])

36. Internal Respiration • Exchange of gases between blood and body cells • An opposite reaction to what occurs in the lungs • Carbon dioxide diffuses out of tissue to blood • Oxygen diffuses from blood into tissue

37. Mechanics of Breathing (Pulmonary Ventilation) • Two phases • Inspiration – flow of air into lung • Expiration – air leaving lung

38. Inspiration • Diaphragm and intercostal muscles contract • The size of the thoracic cavity increases • External air is pulled not sucked into the lungs

39. Inspiration Figure 13.7a

40. Expiration • Largely a passive process which depends on natural lung elasticity • As muscles relax, air is pushed out of the lungs • Forced expiration can occur mostly by contracting internal intercostal muscles to depress the rib cage

41. Expiration Figure 13.7b

42. Nonrespiratory Air Movements • Can be caused by reflexes or voluntary actions • Examples • Cough and sneeze – clears lungs of debris • Laughing • Crying • Yawn • Hiccup

43. Respiratory Sounds • Sounds are monitored with a stethoscope • Bronchial sounds – produced by air rushing through trachea and bronchi • Vesicular breathing sounds – soft sounds of air filling alveoli

44. Factors Influencing Respiratory Rate and Depth • Physical factors • Increased body temperature • Exercise • Talking • Coughing • Volition (conscious control) • Emotional factors

45. Premature births • One of the issues with pre-term birth is the underdeveloped lungs. • Before 22 weeks a fetus’ lungs are too under developed for gas exchange. • 23 weeks is the youngest surviving (it rare & they will have medical issues for life) • 37-40 weeks is considered full term.

46. Emphysema • Alveoli enlarge as adjacent chambers break through • Chronic inflammation promotes lung fibrosis • Airways collapse during expiration • Patients use a large amount of energy to exhale • Overinflation of the lungs leads to a permanently expanded barrel chest • Cyanosis appears late in the disease

47. Chronic Bronchitis • Mucosa of the lower respiratory passages becomes severely inflamed • Mucus production increases • Pooled mucus impairs ventilation and gas exchange • Risk of lung infection increases • Pneumonia is common • Hypoxia and cyanosis occur early

48. Lung Cancer • Accounts for 1/3 of all cancer deaths in the United States • Increased incidence associated with smoking • Three common types • Squamous cell carcinoma • Adenocarcinoma • Small cell carcinoma

49. Sudden Infant Death syndrome (SIDS) • When an apparently healthy infant stops breathing and dies during sleep • Some cases are thought to be a problem of the neural respiratory control center • One third of cases appear to be due to heart rhythm abnormalities

50. Asthma • Chronic inflamed hypersensitive bronchiole passages • Response to irritants with coughing, and wheezing