Flashcards in B2 Healthy Heart & Lungs Deck (18):
What are the two types of the epithelia in the nose, trachea and bronchus?
Respiratory and Olfactory
What are the three types of respiratory epithelia?
What is the olfactory epithelia?
Specialised olfactory cells with a type of neuron that has tentacle like projections to increase SA
True or false? Olfactory cells are replaced regularly?
True - they are regenerated by basal cells
True or false? The nose only has olfactory epithelia?
False- It also has respiratory epithelia
What type of epithelium is in the trachea and bronchi?
What does the majority of the alveolar surface comprise of?
Type I Pneumocytes (Squamous)
What does the air-blood interface comprise of?
Flattened cytoplasm of type I pneumocyte
Fused basal lamina
Flattened cytoplasm of capillary epithelial cell
Why is gas exchange efficient through the air blood interface?
What is the second type of epithelial cell?
Type 2 Pneumocytes
What do type 2 pneumocytes do?
What is the role of surfactant?
Makes SA for diffusion as large as possible
How does surfactant increase surface area?
Decreasing surface tension
What are the other components of alveoli?
Interstitial spaces with elastic fibres
What is the histology of bronchioles?
More cuboidal epithelia with Clara cells replacing goblet cells
What are the particle expulsion mechanisms of the respiratory tract?
Coughing, Sneezing, Cilia
What are the immune defense mechanisms of the respiratory tract?
Lymphoid tissues and IgA