All organisms exchange gases with their environment. Organisms can use simple diffusion to exchange gases when the diffusion pathway is less than 1.0 mm1.0\text{ mm}1.0 mm.
A leatherjacket larva:
Calculate the diffusion pathway (radius) of the larva and state whether it could or could not rely on simple diffusion across its external surface to meet its gas exchange requirements.
Use the formula: \
\text{Volume of a cylinder} = \pi r^2 l{\char"24}$34 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.