The document provides an overview of the anatomy and physiology of the respiratory tract. It begins with an introduction to the main structures including the nose, nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles and lungs. It then describes each structure in more detail, covering their location, composition, blood supply and functions. Key points include a description of the nasal cavities and their three sections, the role of nasal conchae in airflow, and the functions of the respiratory tract in warming, humidifying and filtering air before it reaches the lungs.

1. ANATOMY OF
RESPIRATORY TRACT
BY Ms. Saili Gaude
Principal
Shivam College of Nursing

2. INTRODUCTION
Nose & nasal cavity
Pharynx
Larynx
Trachea
2 bronchi
Bronchioles
2 lungs
Muscles of breathing

3. A
B
C
D
E
F
G
H

4. NASAL CAVITY
Nose – external portion
Nasal cavity – internal portion

5. EXTERNAL NOSE
Root of nose
Dorsum of nose
Apex of nose
Ala of nose

6. EXTERNAL NOSE
Triangular pyramidal shape
Highest point of the nose is referred to as apex or tip of nose
Thin upper part that connects with the forehead is called as the root
Region between apex and root is called dorsum
Small curve below the root is called bridge
Below the apex is nostrils

7. NOSE
BONY PART
• 2 nasal bones – nasale dextrum and sinistrum
• Forms bridge of nose
CARTILIGENOUS PART
• Remainder is cartilegenous part
• Flexible
• Connective and soft tissues

8. 5 CARTILAGES OF NOSE
Lateral nasal cartilage
Major ala cartilage
Minor ala cartilage
Accessory nasal cartilage
Septal nasal cartilage

9. MUSCLES OF EXTERNAL NOSE
1) Procerus muscle- helps depress the medial
eyebrow and wrinkles the skin
2) Nasalis muscle- dilates the nares and flares
them
3) Depressor septi muscles- assists nasalis
muscles

10. BLOOD SUPPLY
ARTERIAL SUPPLY : FACIAL ARTERY – angular and lateral artery
VENOUS SUPPLY: FACIAL VEIN
LYMPHATIC DRAINAGE: DEEP CERVICAL LYMPH NODES

11. NERVE SUPPLY
SENSORY INNERVATION-
Trigeminal nerve
External nasal nerve
Infrorbital nerve
MOTOR INNERVATION:
Facial nerve

12. NASAL CAVITY
Space behind the nostrils
Seperated into right and left nasal cavities by
nasal septum
3 sections of the nasal cavity

13. SECTIONS OF NASAL CAVITY
1) NASAL
VESTIBULE
2) RESPIRATORY
REGION
3) OLFACTORY
REGION

15. VESTIBULE
Area surrounding the anterior external opening
to the nasal cavity
Lined with skin tissue unlike the rest of the
nasal cavity
Surrounded by the wings of nose and the nasal
septum
Floor- hard palate

16. RESPIRATORY REGION
Wide space within the nose covered with
ciliated pseudostratified epithelium
Mixed with mucus secreting goblet cells

18. OLFACTORY REGION
Located at apex of the nasal cavity
Lined by olfactory cells with olfactory receptors
2 patches of olfactory receptors in each nasal
cavity located beneath the 2 olfactory bulbs
This region connects the nose to olfactory
centre of the occipital lobe

21. NASAL CONCHA
Projecting out of the lateral walls of the nasal cavity are curved shelves of
bone. They are called conchae (or turbinates).
The are three pairs of conchae
Inferior Middle Superior

23. INFERIOR CONCHAE
Longest and broadest of the 3 concha
Extends horizontally along lateral wall of the nasal cavity

24. MIDDLE CONCHA
Superior to the inferior concha
Extensions of labyrinth portion of ethmoid bone

25. SUPERIOR CONCHA
Superior to middle concha
Extension of the labyrinth portion of the ethmoid bone

26. NASAL MEATUS
The conchae creates 4 pathways for air flow called as the meatus.
Inferior meatus: between inferior and floor of nasal cavity
Middle meatus: between inferior and middle concha
Superior meatus: between middle and superior concha
Spheno ethmoidal recess: superiorly and posteriorly to superior
concha

27. BOUNDARIES
Each half of the nasal cavity has :
 roof
Floor
Medial wall
Lateral wall
Each half diameter about 5 cm in height , 5-6cm in length, 1.5 cm in
width and 1-2 mm at the roof.
Roof is formed by cribiform plate of ethmoid bone
Floor is formed by palate which seperates oral cavity from nasal cavity

28. OPENINGS
Paranasal sinuses opens into the nasal cavity
All the sinuses except sphenoid sinus drains into the lateral wall. The
sphenoid sinus drains into posterior roof
Nasolacrimal duct also opens into the nasal cavity. Naso is nose and
lacrimal is tear gland
Auditory tube: it opens at the level of inferior meatus.

29. BLOOD SUPPLY
Branches of carotid artery provide the arterial supply
 Internal carotid artery and external carotid artery
 These arteries anatomise with each other in the nasal cavity
Venous drainage
- pterygoid plexus
- facial vein

30. KISSELBACH’S PLEXUS
Also known as the little’s area
It is very vascular area
4 arteries anastomose in this area to form the kisselbach’s plexus
Situated at the anterior inferior part of the nose
Most common site of nose bleed

31. WOODRUFF AREA
It is a plexus of veins
Situated inferior to posterior end of inferior turbinate
Site of posterior nasal bleed

32. BLOOD SUPPLY
Olfactory nerves helps in the sense of smell
 Lies on superior surface of cribriform plate
Nasopalantine nerve
 Maxillary nerve
Nasociliary nerve
Opthalmic nerve
Trigeminal nerve

33. PHYSIOLOGY
The nose is an olfactory and respiratory organ
Consists of nasal skeleton which houses nasal cavity
Functions of nose:
1. warms and humidifies air
2. removes and traps pathogens and smaller particles
3. sense of smell
4. drains and clears sinuses and lacrimal duct
5. increases surface area to allow more air to enter
6. disrupts fast laminar flow of air
7. Allows proper functioning of ears

34. 1. WARMS AND HUMIDIFIES AIR
This is done by the function of concha and the rich blood supply of
the nose.
The blood supply of nose carries heat from the body which is
dissipated into the inhaled air during inhalation
Also the concha slows down the speed of air entering the nose
allowing adequate time for the air to be humdified before it enters
the lungs.

35. 2. REMOVES AND TRAPS
PATHOGEN / PARTICLES
The pseudostratified columnar epithelium with its goblet cells
secretes mucus , a thick sticky substance which traps any pathogen
or particles entering the nose.
The mucociliary action of the pseudostratified columnar epithelium
than causes the removal of the mucus out of the cavity thus not
allowing any micro organism or particle entry into the respiratory
tract.

36. 3. SENSE OF SMELL
The olfactory nerve branches runs through the cribriform plate to
provide sensory innervation to the nose. It thus helps in the sense of
smell.

37. 4. DRAINS AND CLEARS SINUSES
AND LACRIMAL DUCTS
The nasolacrimal system helps to drain the tears formed in the eyes
The paranasal sinuses opens into the nose allowing it to be drained
out into the nasal cavity. This helps in prevention of accumulation of
fluid into the sinuses which can lead to sinusitis

38. 5.ALLOWS MORE ENTRY OF AIR
The nasal concha increases the surface area of the nose which allows
the entry of more air during inspiration

39. 6. DISRUPTS FAST LAMINAR AIR
FLOW
The nasal conchae also helps in reducing the speed of air flow as it
can damage the respiratory tract. The conchae due to its horizontal
pathaways allows a more controlled entry of air.

40. 7. HELPS IN PROPER FUNCTION OF
THE EAR
The eustachian tube (auditory tube) opens into the nasal cavity. It
allows the middle ear to equalise with the atmospheric pressure.