1. The Respiratory System

2. 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

3. 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

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

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

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

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

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

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

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

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

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

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

17. 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

18. Parts of the Pharynx Pharyngeal Tonsils: Palatine 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

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

23. 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

24. 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

26. 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!

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

33.
YouTube - Video Stroboscopy of the Vocal Cords
YouTube - Mythbusters - Helium and Sulfur Hexafluoride

34. 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

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

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

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

38. Parts of Lungs Apex Base Visceral Pleura 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

39. 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)

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