Biology A-Level
Diffusion distance
What Diffusion distance means in Biology A-Level, as defined for OCR.
Definition of Diffusion distance
Check what you remember
Read the wording for your board, then hide it and explain Diffusion distance in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: OCR
The distance from the outside to the centre of an organism, which increases as the organism becomes larger.
Topics that use Diffusion distance
- Exchange surfaces (OCR A-Level)
Related terms
- Adaptations of exchange surfaces
- Airway structure and support
- Alveolar and capillary adaptations for diffusion
- Antagonistic muscle action
- Concentration gradients
- Correct use of the light microscope
- Counter-current gas exchange in gills
- large surface area
Using Diffusion distance in the exam
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