Normal Structure and Function

Question 1

What are the lung mechanics of inspiration?

Answer 1

Increased AP, transverse and vertical diameters of teh thorax –> negative airway pressure –> air inspired down the pressure gradient to the alveoli

Question 2

What are the lung mechanics of expiration?

Answer 2

passive recoil of the chest wall and lung tissues –> generation of positive airway pressure –> air expired down the pressure gradient to the mouth.

Question 3

What are the layers of the airway wall (from outside to lumen)

Answer 3

• Adventitia - made of areolar connective tissue - connects the trachea to soft tissues
• Hyaline cartilage (changes to smooth muscle further down the respiratory tract)
• Submucosa - contains seromucosa glads which produce mucus (no glands in the small bronchioles)
• Mucosa - Internal layer
  of Ciliated pseudostratified columnar epithelium With underlying lamina (elastic and reticular tissues)

Question 4

What is the difference between the left and right bronchi?

Answer 4

Right is more vertical, shorter and wider - more likely to aspirate

Question 5

What are the names of the parts of the respiratory tract?

Answer 5

Bronchi –> Lobar bronchi –> segmental bronchi –> large bronchioles –> small bronchioles –> terminal bronchioles –> alveoli

Question 6

Where is the MCE?

Answer 6

All non-gas change surfaces - from the small bronchioles to the larynx

Question 7

What is the MCE made up of?

Answer 7

inner sol layer - watery substance which allows the cilia to waft

Outer gel layer - consists of sticky layer of mucus

Question 8

What is the role of the MCE?

Answer 8

traps particles in the mucus and then moves them towards the mouth by the wafting of cilia

Question 9

What type of cells make up the MCE?

Answer 9

psuedostratified ciliated columnar epithelium