Lungs

Question 1

Bronchiole Histological Features

Answer 1

• simple cuboidal epithelium
• no cartilage
• no submucosa glands
• no goblet cells
• smooth muscles and elastic fibres

Question 2

Contracted vs Relaxed Bronchiole

Answer 2

Bronchiole = in lung tissue (alveoli)
Contracted – folded simple cuboidal epithelium
Relaxed – larger lumen lined with simple cuboidal

Question 3

What cells do bronchioles contain?

Answer 3

Club cell (Clara cell) = surfactant-like substances to prevent bronchiole sides from sticking
Ciliated Cells

Question 4

Respiratory Bronchiole Features

Answer 4

• part of wall of bronchiole = alveolus
• smooth muscle and elastic fibres
• simple cuboidal epithelium with club cells in lung tissue

Question 5

Alveoli have…

Answer 5

Pores of Kohn
- connect alveoli –> equilibrated pressure = no burst
- for air to escape between alveoli
Capillaries Surround
Squamous Epithelium

Question 6

Alveolar Septum = Air-Blood Barrier

Answer 6

Type II Pneumocyte = produce surfactant (lipid granules)
Endothelial Cell
Basement Membrane
Type I Pneumocyte
RBC in lumen of alveolar capillary

Question 7

Type II Pneumocyte

Answer 7

lamellar body = contain lipid-rich components (stripes)
surfactant = protein lipid complex around cell (wavy)

Question 8

Alveolar Macrophage (Dust Cell)

Answer 8

• phagocytose inhaled particles and antigens trapped in mucus or surfactant