Mass Transport Flashcards
How is surface area to volume ratio affected with size
Increasing size
Decreases SA:V
What is required to organisms with an incredibly low SA:V ratio
Specialist exchange surfaces required to absorb nutrients, respiratory gases and remove excretory products
What is a transport system required to do
Transport materials from:
Cells to exchange surfaces
Surfaces to cells
Surface to environment
Different parts of the organism
What is a specialised transport medium dependent on
SA:V
How active an organism is
What are some common features of large organisms
- Suitable medium to carry materials (blood)
- Form of mass transport (medium carried in bulk over large distances)
- Closed system of vessels
- Mechanism to move transport medium within vessels (pressure difference)
How is transport of medium achieved in animals
Muscular contraction
How is transport of medium achieved in plants
Has mechanism to maintain mass flow movement in one direction
Controlling flow of transport medium
Mechanism for flow of water or gases
What type of circulatory system to mammals have
Closed, double circulatory system
Why is blood passed through vessels twice
So pressure is reduced otherwise circulation would be slow
Why is it good for substances to be passed around the body rapidly
Maintain high body temperature and high rate of metabolism
What’s the final part of the transport system
Diffusion
From blood vessels into cells
Over large SA, short distances so there is a steep diffusion gradient
