Exchange surfaces Flashcards
Mammalian gas exchange system
-Trachea
-Bronchi
-Bronchioles
-alveoli
Adaptations of the trachea
- C shaped rings of cartilage for support
-Ciliated epithelium with goblet cells
-Smooth muscle within the walls of the trachea, muscle contracts if there are harmful substances detected in the air, this results in lumen of the trachea constricting and reducing airflow into the lungs.
-When the smooth muscle relaxes, the lumen dilates
This is due to elastic fibres
Adaptations of the bronchus and bronchioles
The trachea, spilt in two bronchi (one for each lung)
These split into smaller tubes to create a network of bronchioles
Both the B have cartilage withing their walls for structural support and to keep the tubes open
Adaptations of the Alveoli
Located at the end of the bronchioles and are the site of gas exchange
Oxygen diffuses from the alveoli into the blood in the capillaries and CO2 diffuses from the blood in the capillaries to the alveoli
LSA- large number of alveoli’s
Short diffusion distance - the alveoli walls are very thin
Maintains a concentration gradient - Each alveolus is surrounded by a network of capillaries to remove exchanged gases
What is ventilation and what does it do?
Ventilation is the mechanism of breathing which involves te diaphragm and agnostic interaction between the external and internal intercoastal muscles bringing pressure changes in the thoracic cavity
Ventilation maintains the concentration gradient for gas exchange at the alveoli.
What is inspiration in ventilation and what does it do ?
The process of inspiration is results an increased volume inside the thorax. This increased volume therefore means that there will be a drop in air pressure in the thorax. This will cause air to flow into the lungs
What is expiration in ventilation and what does it do ?
In expiration, there is a decrease in volume of the thorax and hence there is an increased air pressure within the thorax. This will force air out of the lungs
What is a spirometer?
A spirometer is something that measures the volume of air inhaled and exhaled
What can be measured using a spirometer?
-vital capacity
-Tidal volume
-Residual volume
-Breathing rate
What is vital capacity?
The maximum volume of air an individual can inhale and exhale during a deep breathe
What is tidal volume ?
The air inhaled (peaks) and exhaled (troughs) when at rest
What is residual volume?
The volume of air that always stays in the lungs so that they dont collapse
What is breathing rate ?
The number of breathes taken per minute
What is oxygen uptake?
Oxygen uptake is something that will increases when the ventilation rate increases, This will occur during exercise.
What are interleukins ?
A chemical through which cells can talk to each other, immune cells talk to each other
