7.9 Investigating Transport in Plants

This resource guides a-level biologists through the experiments that provide evidence that sugars are carried in the phloem. The concept of ringing experiments are explored before discussing its conclusions. We then move onto how radioactive tracers can be used and look at the conclusions drawn from these experiments. Other evidence such as aphids and cutting of phloem are also considered. Stretch, challenge and lateral thinking questions are embedded throughout alongside carefully selected visuals.