1) Ventilation -diaphragm + intercostal and abdominal muscles

2) Conduction -respiratory airways (for warming, moistening, cleaning of debris and mucous)

3) Gas exchange- the air blood interface

From the endodermal diverticulum of the foregut ( an epithelial tube that undergoes branching - Morphogenesis) Consists of

1) series of tubes with epithelial lining

2) lamina propia

3) connective tissue with glands and sometimes cartilege

4) smooth muscle

5) adventitia containing connective tissue

Transports air to the alveoli & to filter, clean, moisten, and warm or cool the air before it reaches the lower respiratory tract. It functions as “anatomic dead space”.

Includes:

Pharynx Trachea,

bronchi, bronchioles, terminal bronchioles.

An irregular cartilage-bound space connecting pharynx to trachea.

Two functions: Phonation (vocalizaton) + control of the air pathway

The major structures

 epiglottis, thyroid cartilage, cricoid cartilage, and bilateral arytenoid cartilages.

-septum divides into two

-turbinates(conchae) divide each of the two chambers into          superior, middle, inferior

         -superior SOB- olfactory epith ( basal (give rise to new               cells), support, olfactory cells)

    -vascular venous plexus "swell bodies" w/in lamina propia

-air is humidified and warmed

- superior = olfactory epith

air filled sinuses - each sinus named for the bone in which it is located

• Maxillary (one sinus located in each cheek)
• Ethmoid (6-12 small sinuses per side, located between
• the eyes)
• Frontal (one sinus per side, located in the forehead)
• Sphenoid (one sinus per side, located behind the
• ethmoid sinuses, near the middle of the skull).
• Each of these sinuses has an opening that connects to the naval cavity called an ostium.
• Like the nasal cavity, the paranasal sinuses are lined with “respiratory epithelium”, though it is a thinner epithelium and contains fewer goblet cells.

Connects the Pharynx to the trachea

Control of air pathway

epiglotis

thyroid 

cricoid cartilege

bilateral a cartilage

• upper most part of larynx
• stratified squamous
• prevents food from entering 
• lower part = resp epith
• - elastic cartilage core and vascularized connective tissue
• exocrine glands in lamina propia
• fibrilar- high density of chondrocytes

• Laryngeal ventrical seperates upper (false) and lower (true) vocal cords
• True- statified squamous elastic ligament and skeletal muscle
• False- respiratory epithelium and a lamina propia that contains mainly exocrine glands
• -sometimes lymphatic nodules

• From larynx to the bifurcation of bronchi
• resp epith
• C shaped hyalin cartilage rings
• smooth muscle and a dense fibroelastic cartilege that is continuous with perichondrium of ring

right branch in ventrical and left is oblique

like the trachea but with o shape ring instead of c

As bronchi divide rings turn into irregular plates

.... the bands of smooth muscle become more prominant

lamina propia with elastic fiber

• no cartilege or glands
• larger have resp epith and smaller have ciliary columnar and then cuboidal epith

• The first and largest
• no cartilege in walls
• ciliated cuboidal 
• clara cells
• lamina propia - lotsa smooth muscle (constrict during asthma) and elastic fibers
• sympathetic promotes dilation

Respiratory Bronchiole

• Short tubes that serve as transition btw conducting and respiratory portion
• Non ciliated simple cuboidal (clara cells)... transitions into squamous at alveolar
• No cartilage or goblet cells
• have smooth muscle
• close association with pulmonary artery - openings in walls

alveolar duct- hallway (elastic +collagen fibers)

Atria/atrium/alveolar sac- foyer at end

alveoli- sack

1) endothelial cells of blood capillaries

2) squamous type 1 epithelial cells

3)secretary type 2 alveolar cells

Common basal lamina btw alveolar and endothelial

simple squamous epithelial that make up most of the lining of alveolar wall

- attached by desmosomes and zonula occludins

cuboidal large rounded cells

have lamellar bodies

found in junctions between walls

contain surfactant which coats alveolar lining to reduce surface tension- premature babies dont have

1)Hypophase-aqueous basal layer

2)Phospholipid phase (dipalmitoyl)