Exchange between organisms and their environment

Created by: emmadallerz
Created on: 03-05-16 20:36

What does a higher SA:V ratio mean in terms of the rate of gas exchange?

Higher SA in comparison to V = better, quicker rate of exchange

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Why do large organisms need a specialised gas exchange system?

Organisms get larger, volume increases quicker than surface area. As a result, simple diffusion can only works for relatively inactive organisms-it would take too long for substances to reach centre of organism if diffusion=sole transport method

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Why would an organism have a flattened shape?

no cell is ever far from the surface

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Name five features of specialised exchange surfaces

1 ^ SA:V-increase exchange rate 2 thin-reduce diffusion distance&rapid crossing of exchange surface 3 selectively permeable 4 movement of environmental medium(air)-maintain diffusion gradient 5 movement of internal medium-maintain diffusion gradient

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Why are specialised exchange surfaces often found inside an organism?

They are often very thin and therefore easily damaged and dehydrated - they need to be protected

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Other cards in this set

Card 2

Front

Why do large organisms need a specialised gas exchange system?

Back

Card 3

Front

Why would an organism have a flattened shape?

Back

Card 4

Front

Name five features of specialised exchange surfaces

Back

Card 5

Front

Why are specialised exchange surfaces often found inside an organism?

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Exchange between organisms and their environment