Structure And Function

Question 1

Describe the structural changes that occur between the conducting and respiratory zones

Answer 1

Cartilage rings are replaced by irregular plates
By the bronchioles no cartilage (smooth muscle)
Pseudostratified to columnar to cuboidal
Resp Bronchioles cuboidal
Resp bronchioles thin & delicate
No mucous cells/ glands
sparse cillia

Question 2

Describe the structure of alveoli

Answer 2

150 million per lungg
connected by pores of kohn
single squamos epithelium
surrounded by a flexible basement membrane
type 2 cells produce surfactant 
no cillia
alveolar macrophages

Question 3

state the functions of the respiratory system

Answer 3

gas exchange
production of surfactant
filters air
blood resivoir
acid/base balance

Question 4

Describe the properties of the lung and what can affect them

Answer 4

Compliance: the ease to which the lungs can be inflated with every unit of pressure. Affected by fibrosis, atelectasis, pneumothorax

Resistance: Composed of airway and tissue resistance, highest in medium sized bronchi. Decreases during inhalation as the lung tissue is connected to the thorax as it expands. Increases during exhalation.

Elasticity: Ability to recoil to original position. Lowered by surfactant.

Question 5

describe the structure of the lower respiratory tract

Answer 5

Trachea
Primary (left & right bronchi) at carina
Secondary (lobar) bronchi at hilum
Tertiary (segmental) bronchi
Bronchioles 1mm
Terminal Bronchioles 0.5mm
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Respiratory Bronchioles
Alveolar duct
Alveolar sac