1. Anatomy of the Respiratory System
Lab Exercise 24
Anatomy of the Respiratory System
Portland Community College
BI 233

2. Upper & Lower Respiratory System
Upper Respiratory System
Nose
Nasal cavity
Paranasal sinuses
Pharynx

3. Respiratory system Lower Respiratory System Larynx Trachea Bronchi
Lungs

4. Nasal bones
Frontal and nasal bones for the nasal bridge and processes of the maxillae make up the lateral walls.
Nasal septum divides the nasal cavity into right and left halves formed by vomer and perpendicular plate of the ethmoid

5. Uvula
During swallowing, the soft palate elevates and the uvula closes off the internal nares, preventing food or fluids from entering the nasal cavity.

6. Nasal Cavity

7. Nasal Cavity Superior Middle & Inferior Turbinates
Opening of Auditory Tube
External Nares

8. Nasal Cavity
The nasal epithelium covering the conchae serves to cleanse, warm and humidify the air
Nasal conchae increase the surface areas for the mucus epithelium
The olfactory epithelium in the upper medial part of the nasal cavity is involved in the sense of smell.
The nasal cavity serves as a resonating chamber as well as an avenue for escaping air.

9. Nasal Turbinates or Conchae
Ciliated pseudostratified columnar epithelium with goblet cells pushes trapped dust toward the back of the throat to be swallowed. .

11. Sinuses
All the sinuses are continuous with the nasal cavity are lined by mucous membrane.
Mucous secretions drain into the nasal cavities.

12. Pharynx
Connects the nasal and oral cavities to the larynx and esophagus
Anatomically divided into 3 sections:
Nasopharynx
Oropharynx
Laryngopharynx

13. (pseudostratified epithelium)
(stratified squamous epithelium)
(stratified squamous epithelium)

14. Tonsils
Pharyngeal Tonsils (Adenoids)
Palatine Tonsils
Lingual Tonsils

15. Tonsils
Pharyngeal tonsils
Tonsils: lymphoid tissue.
Palatine tonsils

16. Larynx: aka Voice Box
Made of 9 pieces of cartilage, the most important are:
Thyroid cartilage (Adam’s Apple)
Thyrohyoid membrane
Cricoid Cartilage
Cricothroid ligament
Epiglottis

17. Larynx Hyoid Bone Thyrohyoid Membrane Epiglottis Thyroid Cartilage
Cricothyroid Ligament
Cricoid Cartilage
Tracheal Cartilage

18. Inside the Larynx Vestibular Folds: Vocal Cords, or vocal folds
Also called false vocal cords, ventricular band of larynx, ventricular folds, and upper folds
Vocal Cords, or vocal folds
Lower, “true” vocal cords
Attach to the arytenoid cartilages by the vocal ligaments (internal)
Glottis: The vocal cords and the space (rima glottidis) between them.

19. Inside the Larynx

20. Inside the Larynx Corniculate cartilage Cuneiform cartilage
Rima Glottis
True Vocal Cords
Glottis
Epiglottis
Tongue

21. Glottis: True cords plus opening Rima Glottis: The opening

22. Airways Larynx Trachea Right Mainstem Bronchi Left Mainstem Bronchi
The carina is the last cartilage which separates the entrances to the left and right primary bronchi
Secondary Bronchi
Carina
Secondary Bronchi

23. Bronchi
The carina of the last tracheal cartilage marks the end of the trachea and the beginning of the right and left bronchi
Left main stem bronchus
Right main stem bronchus
Bronchi subdivide into secondary bronchi, each supplying a lobe of the lungs

24. Respiratory Tree

25. Branching of Bronchial Tree
Trachea
Primary Bronchi
Secondary Bronchi
Tertiary Bronchi
Bronchioles
Terminal/Respiratory Bronchioles

26. Lungs Apex: the part under the clavicle
Base: the part touching the diaphragm
Costal Surface: the part touching the ribs
Hilus: indentation containing pulmonary and systemic blood vessels
Left Lung has 2 lobes and a cardiac notch
Left upper lobe
Left lower lobe
Right Lung has 3 lobes
Right upper lobe, middle lobe, lower lobe

27. Lungs Apex Base LUL RUL Oblique fissure Horizontal fissure
Hilus
Horizontal fissure
Cardiac notch
Oblique fissure
LLL
RML
RLL
Base

28. Lungs: Medial View

29. Lung Lobes

30. Pleura Pleura is the double-layered sac of serous membrane
Parietal Pleura is the outer layer and is attached to the thoracic walls
Visceral Pleura is the inner layer covering the lung tissue
The layers are only touching, they are not fused together
The potential space is called the pleural cavity
There is serous fluid between the layers which allows them to slide against each other during breathing

31. Pleural cavity is in between the two layers

32. Mediastinum The area between the lungs. Posterior to the sternum
Anterior to the vertebrae
Contains the heart, great vessels, esophagus and thymus

33. Trachea Histology Composed of three layers
Mucosa: made up of goblet cells and ciliated pseudostratified columnar epithelium
Submucosa: connective tissue deep to the mucosa
Adventitia: outermost layer, has C-shaped rings of hyaline cartilage

34. Trachea

35. Trachea Histology

36. Trachea Histology

37. Seromucous Glands (Trachea)

38. Trachea Pseudostratified Columnar Epithelium
Submucosa with seromucous glands
Hyaline Cartilage

39. Bronchi Bronchioles Tissue walls of bronchi mimic that of the trachea
As conducting tubes become smaller, structural changes occur and eventually they become bronchioles
Cartilage support structures change
Bronchioles differ from bronchi in that they lack cartilage
Epithelium types change
Amount of smooth muscle increases

40. Bronchi Histology

41. Bronchioles Respiratory Bronchioles
Respiratory Bronchioles : Continued branching leads to the area where gas exchange occurs by simple diffusion

42. Bronchiole Histology Notice the lack of cartilage
Simple columnar epithelium
Notice the lack of cartilage

43. Respiratory Bronchioles Alveolar Ducts Alveolar sacs

44. Alveolar sacs Alveoli Alveolar sacs look like clusters of grapes
The “individual grapes” are Alveoli

45. Alveoli Histology

46. Type II Pneumocytes are cuboidal and produce surfactant
Type 1 Pneumocytes are flattened for gas exchange

48. Respiratory Membrane
The area where gas exchange between air and blood occurs
It is the fused alveolar and capillary walls (3 layers)
Squamous type 1 alveolar epithelium
Fused basal laminae
Squamous endothelial cells in pulmonary capillaries

49. Respiratory Membrane

50. Respiratory System Physiology
Lab Exercise 25
Respiratory System Physiology

51. Terminology
Pulmonary Ventilation: aka breathing, is the movement of air into and out of the lungs
External Respiration: The gas exchange between the blood and alveoli (Partial pressure of oxygen in the alveoli is greater than in the blood)
Transport of gases: which is how oxygen and carbon dioxide are carried by the blood between the lungs and all tissues
Internal Respiration: Exchange of gases between systemic blood and tissue cells (pressures are opposite from external respiration)

52. Dalton’s law
The total pressure of a gas mixture is equal to the partial pressures of all the individual gases in the compound
During respiration, oxygen and carbon dioxide will move along a pressure gradient from high conc. To low conc.

53. Gas Exchange
Almost all oxygen (98%) is transported by binding to hemoglobin in RBCs.
The remainder simply dissolves in the blood plasma.
Most carbon dioxide (68% to 78%) diffuses into RBCs where it is converted to carbonic acid (H2CO3)
Carbonic acid quickly dissociates into bicarbonate ions and hydrogen ions

54. Acid Base Balance in Blood
In the RBC and minimally in the plasma, this reaction takes place
CO2 + H2O  H2CO3  HCO H+
The bicarbonate ions (HCO3- ) help buffer the blood by combining with extra H+ in the blood.
Carbonic acid (H2CO3) releases H+ when the blood becomes too basic.
This way, the balance of H+ remains steady and the pH is doesn’t fluctuate.

55. Carbonic Acid Buffer System: Dealing with Acids
CO2 + H2O  H2CO3  HCO H+
(Add an acid) + H+
The H+ will combine with HCO3- to create H2CO3
H2CO3 will then dissociate into CO2 + H2O
Breathing will increase to rid the body of the extra CO2

56. Carbonic Acid Buffer System: Dealing with Bases
CO2 + H2O  H2CO3  HCO H+
(Add a base) + OH-
The OH- will combine with H+ to create H2O
H2CO3 will dissociate into HCO H+ to restore the H+ concentration

58. Boyle’s Law
The pressure of a gas is inversely proportional to its volume.
If the volume of the thoracic cavity increases, the air pressure in the airways decreases
This results in a pressure gradient that forms between the atmosphere (high) and the air ways (low) forces air to move into the lungs

59. Pulmonary Ventilation
During inspiration, the ribs are elevated and the sternum moves outward.
During expiration, the ribs are depressed and the sternum moves inward.
The diaphragm is the primary inspiratory muscle

60. Inspiration/Expiration
Inspiration: Increase in thoracic cavity size
Inspiratory muscles
External intercostals (lift the rib cage)
Diaphragm (Becomes flat)
Expiration :Decrease in thoracic cavity size
Expiratory muscles
For the most part it is just the relaxation of the inspiratory muscles (passive process)
Internal intercostals & abdominal muscles used only for forced expiration

61. Muscles of Respiration

62. Muscles: Inspiration

63. Muscles: Expiration

64. Spirometry Diagnostic technique used to measure respiratory volumes
The instrument used is a spirometer.
It cannot measure the amount of air in the lung, only the amount entering or leaving.

65. Respiratory Volumes Tidal Volume TV
Volume of air moved in or out of the lungs during quiet breathing about 500 mL.
Inspiratory Reserve Volume IRV
Volume that can be inhaled during forced breathing in addition to tidal volume 3100mL.
Expiratory Reserve Volume ERV
Volume that can be exhaled during forced breathing after a normal tidal volume mL.

66. Respiratory Volumes Residual Volume RV
* Can not be measured using spirometry*
Volume that remains in the lungs at all times 1200 mL.
The sum of two or more of these volumes is known as a pulmonary capacity. The five pulmonary capacities are as follows:

67. Respiratory Capacity Vital Capacity VC
Maximum volume that can be exhaled after taking the deepest breath possible
VC = TV + IRV + ERV
Inspiratory Capacity IC
Maximum volume that can be inhaled after a normal exhalation
IC = TV + IRV

68. Respiratory Capacity Functional Residual Capacity FRC
The amount of air left in the lungs after a normal exhalation
FRC = ERV + RV
Total Lung Capacity TLC
* can not be measured using spirometry*
Total volume of air that the lungs can hold.
TLC = VC + RV

70. Depth and Rate of Ventilation
Eupnea- normal respiratory rhythm
Hypoventilation- caused by breathing either too shallowly or too slowly
CO2 levels increase and pH lowers.
Hyperventilation- a person over ventilates eliminates carbon dioxide faster than it is being produced causing the pH to increase.

71. Activity 25.2
Expiratory capacity is equal to the sum of the tidal volume (TV) and expiratory reserve volume (ERV)
Is the maximum volume of air that can be forcefully exhaled after a normal inhalation.
Practice taking expiratory EC, ERV, TV and VC
Do Activity 25.3: calculate volumes and capacities follow instructions in manual

72. The End
The End