Question 32
Eight similar leaves from the same kind of plant are labelled A–H. Apply petroleum jelly as follows: A/B none; C/D upper surface only; E/F lower surface only; G/H both surfaces. Hang the leaves in their original order and compare their measured mass losses after at least one day. Use your knowledge of leaf structure and transpiration to explain the reasons for the order that you have described in your answer to question 1.
