(a)[3]
Give the names of structures A, B and C.
(b)[1]
Name one visible feature in Fig. 1.1 that would also occur in a prokaryotic cell.
(c)[2]
Cells like the one in Fig. 1.1 are able to divide by mitosis. Describe the role of centrioles in mitosis.
(d)[3]
Sodium ions cross cell surface membranes by facilitated diffusion or active transport. Explain why sodium ions cross cell surface membranes by these mechanisms rather than by simple diffusion.