Structure And Function Of Respiratory Systems Flashcards
What do respiratory systems consist of ?
- Specialised body surfaces for gas exchange (all organisms)
- Mechanism to ventilate the external face of surface (specialised)
- Mechanism to perfuse the internal face of surface (specialised)
What is the rate of diffusion equation ? Ficks law
Q = DA x (Pe-Pi)/L
(Pe-Pi) is the partial pressure difference
A is surface area
L is the thickness of interface
What are the direct relationships in ficks law ?
§ call this direct proportion.
Q § (Pe-Pi)
Q § A
Q § 1/L
What maximises diffusion in animals in liquid environments ?
Gills. They are highly branched and folded extensions of the body surface- evaginations. Increase SA
Thin tissue, so short diffusion pathway.
New medium flows continuously over surfaces.
What maximises diffusion in animals in gaseous environments?
Invaginations- protect respiratory surface. Maximises internal SA.
Thin tissue, minimises diffusion pathway.
Lungs are elastic- increased capacity.
What are the structures of the human respiratory system?
- Nasal cavity
- Pharynx
- Larynx
- Trachea
- Primary bronchus
- Lungs
What does “z” mean in the respiratory tree diagram ?
Generation- division
What is part of the respiratory zone ? What is its role ?
Respiratory bronchioles
Alveolar ducts
Alveolar sacs
For gas exchange
What is part of the conducting zone ? What is it for ? What is another name for it ?
Trachea, bronchi, bronchioles
For filtration and transfer of gases, not gas exchange.
Called dead space
What are consequences of tidal ventilation ?
- Incoming air mixes with ‘used’ gas
- Alveoli provide reservoir of O2
How do birds maximise gas exchange ?
Using unidirectional airflow via air sacs, so it’s always fresh atmosphere air moving across the lungs so greater driving force to take up oxygen.
