Respiration- Gas pressure Flashcards
How do gases move down concentration gradients?
Diffusion
What may concentration gradient be known as?
Pressure gradient
What is the partial pressure of oxygen in anatomical dead space?
150
What is partial pressure?
The pressure that a gas exerts in certain environments
How do you work out partial pressure of gas?
p(gas)= F(gas)in gas mix x barometric pressure
What is the partial pressure of water vapour?
47mmHg
What do you have to take into account when calculating partial pressure in airways?
In airways, air is warmed and humidified and become saturated with water vapour
What happens as you go down divisions in the respiratory tract?
Larger SA
What is the bronchi etc surrounded in?
Cartilage which prevents expansion.
What are conducting airways?
Anatomic dead space not involved in gas exchange
How many alveolar sacs does an adult have?
300-400 million alveolar sacs
What occupies 97% of the SA of alveoli?
Type 1 epithelial cells- primary site for gas exchange
What occupies 3% of alveoli SA?
Type 2 Epithelial cells- Produce Pulamonary Surfactant which reduces surface tension and macrophages
What occupies 3% of alveoli SA?
Type 2 Epithelial cells- Produce Pulamonary Surfactant which reduces surface tension and macrophages
What are the 2 blood supplies to the lungs?
Pulmonary Circulation- Brings deoxygenated blood from heart to lung and oxygenated blood from lung to the heart and rest of body
Bronchial Circulation- brings oxygenated blood to lung parenchyma (lungs cells and tissues)
