Summary of Respiration

Respiration


Structure & Function
Primary Functions
1. Bringing O2 into the body
2. Get rid of CO2
3. Regulate blood pH

Structure
I. Upper respiratory tract
a. Sinuses
b. Nasal cavity
c. External nose
d. Nostril
e. Pharynx
f. Mouth
g. Tongue
h. Epiglottis
i. Glottis
j. Larynx
k. Trachea
l. Oesophagus
II. Lower respiratory tract
a. Trachea
b. Alveoli (tiny, hollow sacs of squamous epithelium; soft & spongy)
c. Rib
d. Two lobes left lung
e. Three lobes right lung
f. Bronchi
g. Bronchioli
h. Diaphragm
i. Pleural membrane + pleural cavity (filled with inner pleural fluid; hydrostatic
pressure allows for easy movement)

Gaseous Exchange
Factors affecting GE
 Surface area of respiratory membrane
 Thickness of respiratory membrane
 Diffusion gradient between two sides
 Diffusion co-efficient or gas (solubility)

Surfactant
- Alveoli contain epithelial cell that secrete a surfactant (a lipoprotein)
- Coats inside of alveoli which reduces surface tension (attraction of water molecules to each
other)
- Without it, alveoli will collapse