The plantain lily, Hosta plantaginea, as shown in Fig. 1.1, is a flowering plant found in Asia. [Figure 1.1] The hydrostatic pressure increases inside guard cells when water enters the guard cells down a water potential gradient. This affects the width of the stomata. Fig. 1.2 shows 1 open stoma from the plantain lily surrounded by 2 guard cells. [Figure 1.2] A student investigated the effect of different sucrose solutions on the width of stomata in the leaves of plantain lily. The student: • prepared 5 microscope slides as shown in Table 1.1 Table 1.1 microscope slide number | liquid added to microscope slide ------------------------- | -------------------------------- 1 | large drop of distilled water 2 | large drop of 2.5% sucrose solution 3 | large drop of 5.0% sucrose solution 4 | large drop of 10.0% sucrose solution 5 | large drop of 20.0% sucrose solution • removed the lower epidermis from a leaf of plantain lily • immersed 1 small piece of lower epidermis in the drop on microscope slide 1 • placed a cover slip over the piece of lower epidermis • observed the stomata using a light microscope fitted with an eyepiece graticule • repeated the steps for microscope slides 2, 3, 4 and 5.