Functions of Respiratory System

• Gas exchange
• Speech/Vocalization
• Smell
• pH of bodily fluids
• Blood pressure regulation
• Promote flow of lymph and venous blood
• Clot prevention
• Urination, defecation, childbirth

Principle Organs of Respiratory System

• Nose
• Pharynx
• Larynx
• Trachea
• Bronchi
• Lungs

Pathway of Airflow Within Lungs

Bronchi - Bronchioles - Alveoli

Divisions of Respiratory System

1. Conducting Division
2. Respiratory Division

Conducting System

Consists of passages that serve only for airflow.

Respiratory Division

Consists of alveoli and other gas-exchange regions of the distal airway.

Upper Respiratory Tract

Nose  - Larynx

Lower Respiratory Tract

Trachea - Lungs

Functions of the Nose

• Warms, cleanses, and humidifies inhaled air
• Detects odors
• Resonating chamber that amplifies the voice

A - Root

B - Bridge

C - Dorsum Nasi

D - Nasofacial Angle

E - Apex

F - Ala Nasi

G - Naris (nostril)

H - Nasal Septum

I - Philtrum

J - Alar Nasal Sulcus

A - Nasal Bone

B - Lateral Cartilage

C - Septal Nasal Cartilage

D - Minor Alar Cartilages

E - Major Alar Cartilages

F - Dense Connective Tissue

Vestibule

• Beginning of nasal cavity
• Small, dialated chamber just inside nostrils
• Lined with Stratified Squamous Epithelium
• Vibrissae are the thick hair that keep debris out

Nares - Nostrils

Nasal Cavity -

• Ethmoid and Sphenoid - Form Roof
• Hard Palate - Forms Floor
• Paranasal Sinuses and Nasolacrimal Duct - Drain into Nasal Cavity

Nasal Septum - Composed of bone and hyaline cartilage.

• Vomer - Inferior Part
• Perpendicular Plate of Ethmoid - Superior Part
• Septal Cartilage - Anterior Part

Middle Nasal Conchae

Inferior Nasal Conchae

Nasopharynx

Soft Palate

Uvula