The document discusses the anatomy and functions of the respiratory system. It describes the major organs that make up the respiratory system including the nose, pharynx, larynx, trachea, lungs and diaphragm. It examines the role of these organs in oxygen intake, carbon dioxide removal, and air conduction throughout the respiratory tract. Key functions like ventilation, gas exchange, and transport are summarized.

2. Objectives
Functional anatomy of respiratory system
Mechanics of breathing
Transport of gases
Regulation of respiration
Pulmonary circulation
Lung function tests
Hypoxia and others conditions
Effect of high barometric pressure
Common disorders of respiratory system

3. Oxygen CellHi I am O2
,you can call
me oxygen, and I will be your guide today.
I advise you keep all feet
and hands inside the ride at all times.
JH

4. Respiratory Intro
You may be asking, what is the Respiratory
system?
Well, the Respiratory system is the system
that helps you breath in and out, so oxygen
(02) can be pumped through your body and
carbon dioxide (CO2) can be removed from
the blood stream.
You must remember that the Respiratory
system is made up of many different organs.

5. Anatomy of respiratory system
• The organs of respiratory system include:
– Nose
– Nasal cavity
– Paranasal sinuses
– Pharynx
– Larynx
– Trachea
– Bronchi and there small bronches
– Lungs which contain alveoli

6. Anatomy of respiratory system
• The organs of respiratory system include:

7. Anatomy of Respiratory System
• Structural classificationStructural classification
– Upper respiratory tract
– Lower respiratory tract
• Functional classificationFunctional classification
– Conducting portion (nose, pharynx,
larynx, trachea, bronchi, bronchioles,
and terminal bronchioles
– their function is to filter, warm, and
moisten air and conduct it into the lungs
– Respiratory portion (Respiratory
bronchioles and the alveolar ducts
are responsible for 10% of the gas
exchange.
– The alveoli responsible for the other
90%)

8. The Respiratory System
• Function of Respiratory systemFunction of Respiratory system
 To provide oxygen (O2) to and eliminate carbon
dioxide (CO2) from the cells of the body.
 Filters, warm and moisten the inspired air
 Produces sound
 Contains receptors for smell
 Rids the body of some excess water and heat
 Helps regulate blood pH

9. The Respiratory System
 Functions to supply the body with O2 and remove CO2
“Respiration” is actually 4 distinct processes:
1. Ventilation – Movement of air into & out of the lungs
2. External Respiration – Gas exchange between blood
and air-filled chambers of the lungs
3. Transport of Gases
4. Internal Respiration – Gas exchange between
systemic blood and the tissue cells

10. The Respiratory System

11. Here is a overview picture of
the Respiratory System.
Just go to the next slide to see
it.
Picture Intro.

12. Respiratory Overview

13. Welcome
Now we will begin our tour.
Welcome to…
MB

14. Nasal Passage
Bronchi Tubes
Alveoli (air-sacs)
Thin-walled blood vessels called
capillaries
Very thin cells line
the alveoli so that O2
and CO2 can pass in
and out of the blood.
Bronchioles pass
air to and from
your alveoli.
The Trachea
is held open
by partial
rings of
cartilage.
Tongue
Pharynx
Where
are We?
We are here.

15. The Nose
• Only externally visible part of the respiratory
system.
• Functions include:
• Providing an airway for respiration
• Moistening and warming air
• Filtering inspired air
• Serving as a resonating center for speech
• Housing the olfactory receptors.

16. Chapter 22, Respiratory System 16
Structure of the Nose
Figure 22.2b

17. The Nose
Cartilages:
Septal cartilage
Nasal cartilage
Alar cartilage(lower
nasal cartilage)
A few minor alar
cartilage
Fibro-fatty tissue in the
lower part of ala

18. 18
Nasal Cavity
• Lies in and posterior to the external nose
• Is divided by a midline nasal septum
• Opens posteriorly into the nasal pharynx via
internal nares
• The ethmoid and sphenoid bones form the
roof
• The floor is formed by the hard and soft
palates

19. The Nasal Cavity
Nasal septum. (Thibodeau/Patton, 2003)

20. The Lateral Walls of Nasal Cavity
1. Inferior meatus:
nasolacrimal duct
2. Middle meatus:
• Maxillary sinus
• Frontal sinus
• Anterior ethmoid sinuses
1. Superior meatus:
posterior ethmoid sinuses
2. Sphenoethmoidal recess:
sphenoid sinus

21. Bones forming lateral wall of nasal cavity
Nasal boneEthmoid bone
Nasal
conchae
Maxilla
Palatine bone

22. Superior concha
Middle conchae
Inferior conchae
Superior
meatus
Middle
meatus
Inferior
meatus
Lateral wall…….contd

23. The Medial Wall of Nasal Cavity
 The Nasal Septum Divides the
nasal cavity into right and left
halves
 It has osseous and
Cartilaginous parts
Nasal septum consists of the
 Perpendicular plate of the
ethmoid bone (superior)
 The vomer (inferior)
 and Septial cartilage (anterior)
Perpendicular
Plate (ethmoid)
Septal
Cartilage Vomer

24. Blood Supply:
External Nose:
Dorsal nasal artery
Angular artery
Superior labial artery
Internal Nose:
Sphenopalatine artery from
maxillary A.
B. Ant. & Post ethmoidal A.
from ophthalmic a.
C. Branches of facial A.
Sphenopalatine a.
Maxillary a.
Veins
Ethmoidal vein------Ophthalmic v.
Other branches---- Pterygoid venous plexus
Facial vein

25. NERVE SUPPLY
 Olfactory nerve
 Anterior ethmoidal nerve
 Nasal branches of pterigo
palatine ganglion
 Nasopalatine nerve
External nose –Infra orbital nerve, Infra trochlear,
External nasal nerve.
Nerve Supply of the Nasal Cavity

26. The Nasal Cavity
• Olfactory region of nasal cavityOlfactory region of nasal cavity
 Olfactory region (Upper 1/3 rd) –The roof of the nasal
cavity, the superior aspect of the nasal septum, and the
superior concha has olfactory epithelium and olfactory
glands.
 mucous membrane lined by pseudostratified columnar
epithelium - more delicate and yellowish.
 The olfactory epithelium is composed of three types of
cells:
 Olfactory cells
 Sustentacular cells
 Basal cells.
 Lamina propria, houses of Bowman’s glands and a rich
vascular plexus.

27. Olfactory Epithelium

28. MUCOUS MEMBRANE
 Lower 2/3 rd – Respiratory region, Lined by pseudo stratified
ciliated columnar epithelium-Thick ,spongy ,highly vascular
with numerous mucous glands contain Goblet cells.
 Goblet cells-function produces mucus
– Contains lysozyme.
– Traps inspired dust, bacteria, and debris.
 High H2O content of mucus humidifies inward air
 Ciliary current moves mucus to pharynx for swallowing.
 Cold temperature disable these cilia  runny nose
 Contains Arteriovenous anastomosis –warms the air passing through it.
 Mucous membrane covering vestibule of nose carries stiff hairs
(Vibrissae).

29. This is where it all begins.
This is where the oxygen first
enters your body and also where
Carbon Dioxide leaves.
The Nose and Mouth
MB

30. The Nose and Mouth
When the air comes into your nose it gets
filtered by tiny hairs and it is moistened by the
mucus that is in your nose.
Your sinuses also help out with your
Respiratory System.
They help to moisten
and heat the air that you breath.
Air can also get into your body through your
mouth/oral cavity but air is not filtered as
much when it enters in through your mouth.
MB

31. The Paranasal Sinuses
• Paranasal Sinuses
– Cavities in cranial bones
• Functions
– Lighten skull bones
– Produce mucus
– Resonate during sound
production
– help warm and moisten air
Each sinus is name after the bone it resides in!

32. Lateral aspects of sinuses

33. Maxillary Sinus
 Pyramidal in shape
 Paired & symmetric
 Located within the body of the
maxilla behind the skin of the
cheek.
 The roof is formed by the floor
of the orbit, and the floor is
related to the roots of the 2nd
premolars and 1st
molar teeth.
 The maxillary sinus opens into
the middle meatus of the nose
 Capacity of 30ml.

34. Frontal Sinuses
 Rarely symmetrical
 Contained within the frontal
bone .
 Separated from each other by
a bony septum.
 Each sinus is roughly triangular
 Extending upward above the
medial end of the eyebrow and
backward into the medial part
of the roof of the orbit.
 Opens into the middle meatus

35. Sphenoidal Sinuses
• Lie within the body of the
sphenoid bone
• Below sella turcica
– Extends between dorsum
sellae and post clinoid
processes
• Opens into the
sphenoethmoidal recess
above the superior
concha

36. Ethmoid Sinuses
• They are anterior, middle, and
posterior
• They are contained within the
ethmoid bone, between the nose
and the orbit
• Anterior & middle
– Drains into middle nasal meatus
• Posterior
– Drain into superior nasal meatus
• Separated from the orbit by a
thin plate of bone so that
infection can readily spread from
the sinuses into the orbit

37. The Pharynx
 Funnel-shaped passageway that connects nasal
cavity and mouth to the larynx and esophagus.
 The muscular wall consists of skeletal muscle.
 Extends from base of the
skull to the level of 6th
cervical vertebrae.

38. The Pharynx
The nasopharynx – air passage
– Lined by respiratory epithelium
• (pseudostratified Ciliated columnar
epithelium)
– Pharyngeal tonsil
– Auditory tube
Oral and laryngeal region
– Passageway for air, food,
and drink
– Stratified squamous epith.

40. Nasopharynx
• Boundaries:
• Roof: body of sphenoid &
basal part of the occipital
bone
• Floor: upper surface of soft
palate and pharyngeal
isthmus

41. Oropharynx
• Lies behind the mouth
• Extends from soft palate to
upper border of epiglottis
• Boundaries:
• Roof: Soft palate and
pharyngeal isthmus
• Floor: Posterior one third of
tongue, median & lateral
glossoepiglottic folds

42. Laryngopharynx
 Lies behind the laryngeal inlet & the
posterior surface of larynx
 Extends from upper border of
epiglottis to lower border of cricoid
cartilage
 Boundaries:
 Anterior wall: mucosa surface of the
posterior surface of larynx
• Posterior wall: supported by bodies of
C3, 4, 5, 6 vertebrae
• Lateral wall:
 Supported by thyroid cartilage and
thyrohyoid membrane

43. Pharyngeal Wall
 It is a musculo-membranous
wall, composed of:
 Mucosa & submucosa
 Pharyngobasilar fascia
 Muscles: circular &
longitudinal
 Buccopharyngeal fascia

44. Nerve supply of the pharynx
Motor supply
Cranial part of accessory nerve
Glossopharyngeal nerve.
Recurrent laryngeal nerve
External laryngeal nerve.
Sensory supply
Pharyngeal branch of pterygo-palatine ganglion.
Glossopharyngeal nerve.
Internal laryngeal nerve.

45. Blood supply of the pharynx
a)Ascending pharyngeal artery
b)Facial artery
c)Maxillary artery.
d) Lingual artery

46. 46
The Larynx (Voicebox)
 Extends from the level of the 4th
to the 6th
cervical
vertebrae
 Attaches to hyoid bone superiorly
 Inferiorly is continuous with trachea (windpipe)
 Three functions:
1. Produces vocalizations (speech)
2. Provides an open airway (breathing)
3. Switching mechanism to route air and food into proper
channels
• Closed during swallowing
• Open during breathing

47. 47
• Framework of the larynx
 9 Cartilages connected by membranes and ligaments
 Thyroid cartilage with laryngeal prominence (Adam’s apple)
anteriorly
 Cricoid cartilage inferior to thyroid cartilage: the only
complete ring of cartilage: signet shaped and wide
posteriorly

48. 48
Behind thyroid cartilage and above cricoid: 3
pairs of small cartilages
1. Arytenoid: anchor the vocal cords
2. Corniculate
3. Cuneiform
– 9th
cartilage: epiglottis

49. 49
Epliglottis* (the 9th
cartilage)
Elastic cartilage covered by mucosa .On a stalk attached to thyroid cartilage
Attaches to back of tongue
During swallowing, larynx is pulled superiorly Epiglottis tips inferiorly to cover
and seal laryngeal inlet to Keeps food out of lower respiratory tract

50. 50
*
*
Posterior views

51. 51
• Cough reflex: keeps all but air out of airways
• Low position of larynx is required for speech (although
makes choking easier)
• Paired vocal ligaments: elastic fibers, the core of the
true vocal cords

52. 52
• Pair of mucosal vocal folds (true vocal cords)
over the ligaments: white because avascular

53. 53
• Innervation of larynx (makes surgery at neck risky)
– Recurrent laryngeal nerves of Vagus
– Vagus nerve
– Damage to one: Hoarseness
– Damage to both: can only Whisper

54. Arterial Supply
Sup. Laryngeal
Inf. Laryngeal A

55. The Larynx
Histology Structures
Epithelial lining:
Superior portion of larynx is lined by stratified squamous
epithelium
Below the vocal folds – pseudostratified ciliated
columnar epithelium.

56. Next lecture: Trachea