1.1. Figure 4 shows two guard cells surrounding an open stoma and two guard cells surrounding a closed stoma.

Figure 4

When light intensity is low, the stoma closes.

Describe how the stoma close.

1.2. Guard cells have cell walls with unevenly distributed cellulose.

Suggest why this is important.

1.3. A student investigated the effect of varying concentrations of salt solution on the opening of stomata on the lower epidermis of a leaf.

Her results are shown in Table 2.

Table 2

The student calculated one of the percentages for open stomata in the field of view incorrectly.

Identify for which solution the result was incorrect and give the correct value.

1.4. Write a conclusion for the results of the experiment as shown in Table 2.

1.5. The student measured the real diameter for the field of view to be 0.475 mm.

Calculate the total number of stomata per mm² of the leaf epidermis placed in 0.8 mol / dm³ salt solution if the value of π (pi) is 3.14.

Show your working.