1. The RESPIRATORY System

2. Respiration
The exchange of gases between the atmosphere, blood, and cells
Pulmonary Ventilation - the exchange of air between the atmosphere and lungs
External (Pulmonary) Respiration - gas exchange between the lungs and blood
Internal (Tissue) Respiration - gas exchange between the blood and cells

3. Functions of the Respiratory System
Provides structures and mechanisms for gas exchange
Intake of O2
Elimination of CO2
Helps maintains body’s pH
Sense of smell
Speech and sound production

4. Organs of the Respiratory System
Nose
Pharynx
Larynx
Trachea
Bronchi
Lungs

5. Respiratory System

6. Respiratory Structures

7. Nose External Portion Internal Portion - large cavity within the skull
Supporting bony framework
Cartilage - Skin
Mucous membranes
Nostrils or external nares
Internal Portion - large cavity within the skull
Connects the external nose to the pharynx through two openings (Internal Nares)

8. External Nose Structures

9. Nose
Nasal Cavity - large cavity that contains both the external and internal nose cavities
divided into the right and left sides by the NASAL SEPTUM

10. Internal Nose Structures

11. Functions of the Nose Warming, moisturizing and filtering incoming air
Smell (reception of olfactory stimulus)
Resonating chamber for speech

12. Pharynx Funnel-shaped tube about 13 cm long
Extends from the internal nares down to the cricoid cartilage of the larynx
Walls composed of skeletal muscle lined with a mucous membrane
Divided into three areas
Nasopharynx
Oropharynx
Laryngopharynx

13. Regions of the Pharynx

14. Functions of the Pharynx
Passageway for food and air
Resonating chamber for speech

15. Larynx (Voice Box)
A short passageway that connects the pharynx with the trachea
Walls of the larynx is composed of 9 pieces if cartilage
Three single pieces of cartilage
epiglottic cartilage (Epiglottis)
thyroid cartilage (Adam’s Apple)
cricoid cartilage (attaches the Larynx to the Trachea)
Three paired pieces of cartilage
arytenoid - corniculate - cuneiform

16. Larynx Structures

17. Trachea Tubular passageway about 12 cm long and 2.54 cm in diameter
Anterior to the esophagus
Extends from the larynx to about the 5th thoracic vertebrae
Composed of C-shaped cartilage rings stacked upon one another
Hyaline cartilage rings
Covers the anterior and lateral walls

18. Trachea and Esophagus

19. Trachea
Non-cartilaginous posterior softer portion of the trachea allows for expansion of the esophagus during swallowing
Lined with ciliated epithelium
The point where the trachea bifurcates is called the carina
About the 5th thoracic vertebrae

20. Bronchi
Tubes that branch off of the trachea at the carina and extend into the lungs
Left Primary Bronchus (Left Mainstem Bronchus)
Right Primary Bronchus (Right Mainstem Bronchus)
Shorter and more vertical
Swallowed objects more likely to lodge in the right primary bronchus than the left

21. Bronchi Also composed of cartilaginous rings
Continue branching as they enter the lungs into a structure called the bronchial tree
Trachea Mainstem (Primary) Bronchi Secondary (Lobar) Bronchi Segmental (Tertiary) Bronchi Terminal Bronchioles Respiratory Bronchioles Alveolar Ducts

22. Bronchial Tree

23. Bronchioles
Bronchioles are smaller air passages which branch from the bronchi. Bronchioles are small, muscular tubes with a narrow diameter. Changes in the size of the bronchioles help direct the flow of air to various parts of the lungs.

24. Alveolar Ducts
Alveolar ducts are enlarged chambers found at the end of the bronchioles. These very fine passageways end at the alveolar sacs and connect to the alveoli.

25. Alveoli A cup shaped out pouching of epithelial tissue
Place where external respiration occurs (gas exchange between the lungs and the blood)
Lungs contain million alveoli
Surface area of about 750 sq. ft.
The size of a Tennis Court

26. Alveoli

27. Pharynx Funnel-shaped tube about 13 cm long
Extends from the internal nares down to the cricoid cartilage of the larynx
Walls composed of skeletal muscle lined with a mucous membrane
Divided into three areas
Nasopharynx
Oropharynx
Laryngopharynx

28. Structures of the Larynx
Epiglottis
Glottis
Hyoid Bone
Thyroid Cartilage
Cricoid Cartilage
True and False Vocal Cords

29. Epiglottis
Large leaf-shaped piece of cartilage lying on top of the larynx
The stem of the epiglottic cartilage is attached to the thyroid cartilage
Leaf portion of the cartilage is unattached and acts like a trap door covering the opening to the trachea which is called the glottis.
Dependent upon breathing or swallowing

30. Epiglottis

31. Glottis
The opening from the pharynx to the larynx that contains the vocal cords
Vocal Cords - mucous membrane folds that extend across the glottis in two layers
upper layer or folds - false vocal folds
lower layer or folds - true vocal folds
Sounds originate from vibration of these true vocal cords

32. Glottis and Vocal Cords

33. Hyoid Bone
Is located in the neck between the lower jaw and the larynx.
It does not articulate with any other bones.
It serves as the posterior attachment for the tongue and helps in swallowing.

34. Thyroid Cartilage
The thyroid cartilage is the largest cartilage of the larynx.
It give the larynx its characteristic triangular shape.
Nicknamed the Adam’s Apple because of its enlarged size due to the influence of testosterone.

35. Cricoid Cartilage The most inferior cartilage of the larynx.
Used as a landmark to perform a tracheotomy.

36. True Vocal Cords
The most inferior of the horizontal folds in the larynx.
Contain elastic fiber which vibrate to create sound.

37. False Vocal Cords The most superior of the folds in the larynx.
Help the glottis close during swallowing to prevent food from entering the lower respiratory passages.

38. Lungs
Paired - cone shaped organs that occupy most of the thoracic cavity
Separated from each other by the heart and other structures of the mediastinum
Surrounded by a double layered serous membrane called the pleural membrane

39. Features of the Lungs
Apex - the pointed, superior portion of the lungs.
Base – the broad, inferior surface of the lungs which rests on the diaphragm.

40. Lungs

41. Left Lung

42. Pleural Membrane Parietal Pleura - outer layer of the pleural membrane
Attached to the thoracic wall
Visceral Pleura - inner layer of the pleural membrane
Attached to the lungs themselves
Between the parietal pleura and the visceral pleura is a potential space called the pleural cavity
Contains pleural (serous) fluid (reduces friction)

43. Gross Anatomy of the Lungs
Extend from the diaphragm to an area about 2.54 cm above the clavicles on both sides of the thoracic cavity
Base
Apex
Hilus
Lobes

44. Lobes and Fissures
Each lung is divided into lobes by one or more fissures
There are three lobes in the right lung and two lobes in the left lung.

45. Pleural Cavity
The mediastinum divides the thoracic cavity into two pleural cavities, each of which contains one lung.

46. Gas Exchange
Gas exchange occurs in the alveoli due to the difference in the partial pressures of oxygen and carbon dioxide in the capillary blood and the alveoli.
Since the concentration of oxygen is greater in the alveoli, it diffuses into the capillary blood.

47. Since the level of carbon dioxide is higher in the capillary blood than in the alveoli, carbon dioxide diffuses out of the blood and into the alveoli.

48. Lung Parameters
Tidal Volume (TV) ml - volume of air moved in and out of the lungs during breathing
Vital Capacity (VC) ml - maximum volume of air that can be exhaled after taking the deepest possible inhalation VC - TV + IRV + ERV

49. Spirometry

50. Physiology of Ventilation
Ventilation - the process of inhaling and exhaling air in and out of the lungs
Pulmonary Ventilation - the process by which air flows between the lungs and the external environment
Due to a change in pressure between the atmosphere and the air in the lungs

51. Physiology of Ventilation

52. Inspiration (Inhalation)
Bringing air into the lungs from the external environment
The lungs themselves contain no muscles and thus depend upon the relationship with the muscles of the walls of the thoracic cavity to alter lung volumes

53. Ventilation

54. Muscles of Ventilation

55. Expiration (Exhalation)
Movement of air from the lungs to the external environment
Normally a passive process (no energy or muscular contractions required)
Dependent upon muscle and lung elasticity
May become active during high levels of physical activity
Most people require ventilation rates above % - 65% of their vital capacity for expiration to become active

56. Physiology of Respiration

57. Respiratory Center

58. Chemical Stimuli
Determines how fast and how deeply an individual breathes
Very sensitive to the levels of CO2 and H+ ion concentration in the blood
Monitored by chemoreceptors at:
carotid arteries, aorta, and the medulla oblongata.

59. Ventilatory Homeostasis

60. RESPIRATORY DISORDERS AND HOMEOSTATIC IMBALANCES

61. Bronchiogenic Carcinoma (Lung Cancer)
Most fatal cancer in the U.S.
Highly metastatic
Usually linked with cigarette smoking
Starts in the walls of the bronchi due to irritation of the bronchiole epithelium
Common irritants include smoking, pollution, dust particles
20 times more prevalent in smokers than non- smokers

62. Emphysema “Blown up or full of air”
A condition where the alveolar walls lose their elasticity and remain filled with air during expiration
Alveoli become damaged and eventually merge together to form large air sacs with reduced overall volume
Patients often develop a barrel chest
Generally caused by cigarettes, pollution, industrial dust particles

63. Influenza •Caused by one of many viruses Antibiotics cannot help
Medications used to treat the symptoms
sneezing - coughing
congestion - rhinorrhea
May result in rhinitis: inflammation of the nasal mucosa
Commonly known as the flu

64. Pneumonia Acute infection or inflammation of the alveoli of the lungs
Most common infectious cause of death in the U.S.
Alveolar sacs fill with fluid and dead white blood cells reducing the amount of functional surface area of the lungs
Most commonly caused by bacterium
Streptococcus pneumoniae
Affects those in poor health or compromised immune system

65. Sudden Infant Death Syndrome (SIDS)
10,000 infant deaths per year in the U.S.
Cause is not known but thought to be caused by an infectious agent or compressed carotid artery
Most deaths occur in the fall or winter
Over 50% of SIDS death children had an upper respiratory infection within the past two weeks
May also be caused by improper positioning for sleeping in the crib

66. Tuberculosis (Tb) Caused by a bacterium
Mycobacterium tuberculosis
An infectious communicable disease that destroys the lung tissue and pleura
Replaced by fibrous connective tissue called tubercles
Disease is spread by inhalation of the bacterium