Some students observed a flowering plant and noticed that the flower was supported by a long stalk. To investigate how the stalk supported the flower, the students first cut transverse sections of the stalk. The students then used a light microscope to observe the transverse sections of the stalk. [Figure 1.1] shows a plan diagram of a transverse section of the stalk. [Figure 1.2] shows the appearance of two cells from each of the layers. The students cut out a piece of stalk that was 40mm long and then split this lengthways into 4 strips, as shown in [Figure 1.3]. The students observed that the strips immediately curved lengthways so that the epidermis was on the inside of the curve. All the strips were put into a Petri dish containing water and left for a period of time. After soaking in water, the strips curved even further. [Figure 1.4] shows the appearance of a strip after being soaked in water, viewed from one end.