(a)[2]
On Fig. 1.1, add label lines and letters to indicate: A - a cell in the epidermal layer. B - a cell containing PEP carboxylase.
(b(i))[1]
Identify the cell type marked C in Fig. 1.1.
(b(ii))[4]
Explain how the leaf structure shown in Fig. 1.1 adapts the C4 plant to sustain a high rate of photosynthesis at high temperatures.
(c(i))[4]
Using Fig. 1.2, compare the rates of photosynthesis in high $\text{CO}_2$ conditions for the C3 and C4 plants.
(c(ii))[2]
Using Fig. 1.2, compare the rates of photosynthesis in low and high $\text{CO}_2$ conditions in the C4 plant between $30\,^{\circ}\text{C}$ and $35\,^{\circ}\text{C}$ and suggest a reason for this difference.