Exchange And Transport Flashcards
How do you calculate the surface area of a sphere?
4 x pi x radius squared
Why do large organisms need an exchange system?
Because they have a larger SA:V, and so have higher energy and oxygen demands where diffusion is not enough as it cannot diffuse the great distance. Larger organisms have higher metabolic activities.
How is alveoli adapted for gas exchange?
- large SA
- thin (1 cell thick got fast diffusion)
- good blood supply (lots of capillaries)
- ventilation (maintains high diffusion gradient)
What is the purpose of the ciliates epithelium and goblet cells?
To secrete mucus and trap bacteria. It is then wafted away and swallowed.
What is the main airway that provides support called?
Trachea
What structures are found in the bronchioles?
Smooth muscle, elastic fibres, flattened epithelium, some ciliated epithelium
Does the bronchi have cartilage?
Yes it has small c shaped cartilage
Why does the alveoli have elastic fibres?
So that it can stretch to allow air in and return to its original size. This is elastic recoil
True or false: inspiration is a passive process.
FALSE it is an active process. Expiration is passive
Name 3 things that happen during inspiration.
- the volume of the thorax increases so pressure decreases and air is drawn in
- diaphragm contracts
- ribcage moves upwards and outwards
How is air drawn out during expiration?
The volume of the thorax decreases so the pressure increases above atmospheric and air is drawn out
What does the peak flow meter do?
Measures the rate that air can be expelled from the lungs.
What is the purpose of soda lime in a spirometer?
To absorb the carbon dioxide.
What is tidal volume?
The volume of air in each breath.
How do you calculate the breathing rate?
Ventilation rate / tidal volume
