Cambridge Secondary (7-9). Stage 9. Science. Learner's Book - Unit 1: Photosynthesis and the carbon cycle - Question 29

Which surface of a leaf has most stomata? Work with a partner for this activity. Put some warm (not hot) water into a beaker or glass. Take a fresh leaf, and push it down under the water. Discuss these questions with your partner. If most bubbles came from one surface of the leaf, why do you think this happened?