2. The Respiratory System

3. Respiratory System Functions
Gas exchange: Oxygen enters blood and carbon dioxide leaves
Regulation of blood pH: Altered by changing blood carbon dioxide levels
Voice production: Movement of air past vocal folds makes sound and speech

4. Respiratory System Functions
Olfaction: Smell occurs when airborne molecules drawn into nasal cavity
Protection: Against microorganisms by preventing entry and removing them
Temperature regulation: Panting in some animals

5. Parts of the Nose
Nose
Only externally visible part of the respiratory system
Job is to begin warming, purifying, and humidifying air

6. Parts of the Nose External Nares (nostrils) Where air enters the nose
The openings
Nasal Cavity
Interior of the nose
Has thin-walled blood vessels to begin warming air

7. Parts of the Nose
Nasal Septum
Midline dividing nasal cavity into two

8. Parts of the Nose Respiratory Mucosa Sticky mucous
Moistens air and traps bacteria & debris
Ciliated cells move mucous back toward throat

10. Parts of the Nose Conchae Mucosa-covered projections
Increase surface area & air turbulence
Provide more opportunity for warming & filtration

11. Parts of the Nose Hard Palate
Anterior separation of nasal & oral cavity
Supported by bone
Soft Palate
Posterior separation of nasal & oral cavity

12. Cleft Palate
Palate does not fuse together
Can also affect the lip

14. Parts of the Nose Paranasal Sinuses Openings in skull bones
Lighten the skull
Resonance chambers for speech
Produce mucus

16. Parts of the Pharynx Pharynx Muscular passageway for food & air
“Throat”
About 5 inches long
Broken into 3 parts

17. Parts of the Pharynx Internal Nares
Opening between nasal cavity and pharynx

18. Parts of the Pharynx Nasopharynx Oropharynx Laryngopharynx
Three divisions of Pharynx
Listed from superior to inferior
After passing through, air enters larynx, food enters esophagus

19. Parts of the Pharynx Pharyngeal Tonsils: AKA adenoids
High in the nasopharynx
Trap bacteria/pathogens
Palatine Tonsils
In oropharynx, end of soft palate
When you get your tonsils out, this is what is removed
Lingual Tonsils
Base of the tongue

22. FYI: Tonsilitis
Catch too much bacteria; palatine tonsils can’t keep up!
EEW.

24. Larynx AKA Voice Box Routes air and food into proper channels
Inferior to pharynx
Formed by 8 rigid cartilages and a spoon-shaped flap of elastic cartilage (epiglottis)
Thyroid cartilage = Adam’s apple

25. Epiglottis Cartilage flap of larynx; protector! When not swallowing:
Epiglottis flapped up
Does not block larynx
When you are swallowing:
Larynx rises
Epiglottis falls
Larynx closed off
This means that food is directed into esophagus

27. FYI: If anything other than air tries to enter the larynx, a cough reflex is triggered to get it out and prevent it from going into the lungs!

31. Vocal Folds Vocal Folds Formed from folds in larynx membrane
Vibrate with expelled air
Glottis
Slit-like passageway between vocal folds

34.
YouTube - Video Stroboscopy of the Vocal Cords
YouTube - Mythbusters - Helium and Sulfur Hexafluoride

35. Trachea
AKA windpipe
Has cartilage rings around it to keep it open during pressure changes
About 4 inches long
Lined with ciliated mucosa to propel mucus (with dust particles & debris) away from the lungs to the throat

36. Primary Bronchi Two (right & left) Formed by division of trachea
Enters the lung, and then breaks off into secondary bronchi

37. Mediastinum Most central area of the thoracic cavity
Includes heart, great blood vessels, bronchi, esophagus, etc. (everything except lungs)

38. Lungs Site of gas exchange Soft & Spongy, only weigh about 2 ½ pounds
Each lung divided into lobes
Left: 2 lobes
Right: 3 lobes

39. Parts of Lungs Apex Narrow superior portion By clavicle Base
Wide inferior portion
Rests on diaphragm
Visceral Pleura
Covers surface of lung
Along with parietal pleura, provides attachment and eliminates friction

40. Bronchial Tree Bronchioles
All of the branching of respiratory passageways in the lungs
Divisions include
Primary bronchi
Secondary bronchi
Tertiary bronchi
Bronchioli
Terminal bronchioli
(end in alveoli)

44. This image is showing the carina – the point where the primary bronchi break off from each other.

45. Alveoli
“Air Sacs”
Resemble bunches of grapes
Make up bulk of lungs

48. Respiratory Zone
Includes respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli
Only places where gas exchange occurs

49. Walls of Alveoli
Made of single, thin layer of squamous epithelial cells
Covered with a cobweb of pulmonary capillaries

50. Respiratory Membrane Made up of alveolar and capillary walls
Has air flowing on one side, blood flowing on the other
Gas exchange occurs through simple diffusion
Oxygen from alveolar air to capillary blood
Carbon dioxide leaving blood to air
FUN FACT: total surface of alveoli walls is about square meters - about the surface of a tennis court!

53. http://highered. mcgraw-hill

54. Steps to Respiration 1. Pulmonary Ventilation (breathing)
Air move in and out of lungs so alveoli air is refreshed
2. External Respiration
Gas exchange between blood and alveoli air
3. Respiratory Gas Transport
Gas transport between lungs and body by bloodstream
4. Internal Respiration (Cellular Respiration!)
In body, at capillaries, gas exchange between blood and tissue cells

55. Respiration Inspiration Expiration
Air flowing into lungs (breathe in!)
Expiration
Air leaving the lungs (breathe out.)
Volume changes lead to pressure changes, which lead to the flow of gases to equalize the pressure!

56. Inspiration Diaphragm and external intercostals contract
Diaphragm actually moves DOWN when contracts
Thoracic cavity size increases
Rib cage lifts
Intrapulmonary volume increases
Gas molecules spread out due to increased volume! This causes a decrease in pressure, which pulls in more gas.

57. Inspiration

58. Expiration Diaphragm and external intercostals relax
Internal intercostals and abdominal muscles contract if expiration is forced
Thoracic cavity size decrease
Rib cage descends
Intrapulmonary volume decreases
Gas molecules get closer together due to the decrease in volume! This causes a increase in pressure, which forces gas out.

59. Expiration

60. Non-Respiratory Air Movements
Cough
Sneeze
Crying – release of air in short breaths
Laughing – release of air in short breaths
Hiccups
Yawn

61. Lung Development Fetus Birth All respiratory exchange made by placenta
Lungs filled with fluid
Birth
Fluid drained, passageways fill with air
Surfacant: fatty molecule that lines each alveolar sac to prevent from collapsing (don’t have enough of this until fetus is 30 weeks)
Lungs do not fully inflate for 2 weeks after birth
20 to 40 respirations/min

62. Lung Development Teens Elderly
12 to 18 respirations/min (rates differ depending on source)
Continue to develop alveoli (smoking stops this production!)
Elderly
Chest wall becomes rigid, lungs lose elasticity, cilia in trachea less effective
Vital capacity decreases
More at-risk for respiratory tract conditions
18 to 20 respirations/min

63. Respiratory Conditions
Pulmonology – study of diseases of the lungs and respiratory tract
Hypoxia – inadequate oxygen delivery to body tissues, causes cyanosis (bluish-tone of skin)

64. Upper Respiratory Tract Infection
Includes things like the common cold, sinusitis, tonsillitis, and laryngitis
Symptoms include nasal congestion, cough, running nose, sore throat, fever, facial pressure, and sneezing

66. Lung Cancer 1/3 of all cancer deaths in the US
Very low survival rate, because usually not caught until very advanced
Growth usually occurs in the bronchial tree
Problem with smoking…
Kills off cilia that cleans & moves mucus out of airway
Mucus collects
Traps carcinogens from cigarettes

70. COPD Chronic Obstructive Pulmonary Disease
Characterized by limited airflow
Symptoms include coughing, wheezing, and shortness of breath (dyspnea)
Usually have a history of smoking, but can also be caused by other inhalants (coal, asbestos, air pollution)

71. COPD
Patients retain carbon dioxide, meaning blood becomes slightly acidic
Usually results in respiratory failure
Two major types (there are other types, but these are the most common)…

73. Emphysema
Characterized by breakdown of elastin in connective tissue of lungs
Leads to destruction of alveolar walls
Lungs become less elastic, which makes it difficult to exhale

75. Chronic Bronchitis Characterized by inflammation of the bronchi
Mucosa lining of lower respiratory passages become inflamed and produces excess mucus, which leads to blockage
Symptoms include persistent coughing with sputum, cyanosis very common

77. Acute Bronchitis Caused by virus or bacteria Only last days/weeks
Symptoms same as chronic bronchitis

79. Pneumonia
Characterized by: Inflammatory illness of the lungs, alveoli become filled with fluid
Varied causes, including bacteria, virus, fungi, chemical, & physical
Often diagnosed with chest x-ray

81. Asthma
Characterized by airways constricting due to trigger (exposure to allergens, pollutants, cold air, warm air, moist air, exercise, or emotional stress)
Symptoms include wheezing, shortness of breath, chest tightness, and coughing
Scientists believe cause is combination of genetics and environment
Inhalers act as bronchodilator

83. Sleep Apnea Characterized by pauses of breathing during sleep
5 or more events, lasting at least 10 seconds each
Caused by blockage of the airways due to causes such as decreased muscle tone, increased soft tissue around airway (obesity), and structural features (deviated septum, enlarged tonsils)

84. Carbon Monoxide Poisoning
Competes with oxygen for same binding sites on hemoglobin
Binds VERY easily, and so it pushes out oxygen
Leading cause of death from fire
Victim usually becomes confused, has headache, and blushing of skin

85. 1 in 20 people are unaffected carriers!
Cystic Fibrosis
Cystic Fibrosis is a recessive genetic disease that effects both the digestive and respiratory system.
Abnormally thick mucus gets stuck in many places. Most commonly in the lungs & pancreatic duct
Symptoms can include persistent coughing, shortness of breath and frequent upper respiratory infections.
1 in 20 people are unaffected carriers!

86. Cystic Fibrosis Easily diagnosable with a sweat test
Treatment for the GI tract involves taking digestive enzymes before eating.
Treatment for the lungs is called CPT, Chest Physiotherapy.
A light clapping of the chest, back, and under the arms to loosen mucus in the lungs