Biology GCSE
diffusion distances
What diffusion distances means in Biology GCSE, as defined for OCR.
Definition of diffusion distances
Check what you remember
Read the wording for your board, then hide it and explain diffusion distances in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: OCR
The distance from the exterior to interior tissues becomes far too great for diffusion alone to supply oxygen or remove toxic urea.
Topics that use diffusion distances
- The challenges of size (OCR GCSE)
Related terms
- active transport of minerals
- arteries
- blood plasma
- boundary layer
- compound measures
- double circulatory system
- erythrocyte adaptations
- Exchange surfaces
Using diffusion distances in the exam
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