Gas exchange in active aquatic invertebrates is often constrained by diffusion rates. For a particular group of marine bristle worms, simple diffusion across the body surface is only sufficient to sustain respiration if the maximum diffusion distance (the radius of the body) does not exceed 0.45 mm0.45\text{ mm}0.45 mm.
A specimen of a newly discovered species of cylindrical bristle worm has the following dimensions:
Calculate the diffusion pathway (radius) of this worm to 2 decimal places, and determine whether it could or could not rely solely on simple diffusion across its body surface for gas exchange.
Use the formula:
Volume of a cylinder=πr2l \text{Volume of a cylinder} = \pi r^2 l Volume of a cylinder=πr2l34 exam-style questions on OCR A A Level Biology Exchange surfaces. Each one has a worked solution and a mark scheme showing where the marks go.