4 2 The diagram shows the ultrastructure of an animal cell. U T S R Q P Magnification ×9000 (a) (i) The structure labelled R on the diagram represents a (1) A chloroplast B lysosome C mitochondrion D ribosome (ii) The structure labelled Q on the diagram represents the (1) A cell surface membrane B nuclear envelope C rough endoplasmic reticulum D smooth endoplasmic reticulum (iii) Calculate the actual diameter of the structure labelled U. (2) Answer .............................................................. 5 Turn over (iv) Describe how the structures labelled P, S and T are involved in the production and secretion of molecules from this cell. (3) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (b) Which row in the table is correct for structures found in animal cells and prokaryotic cells? (1) Nucleolus Plasmid Ribosome Animal cell Prokaryotic cell Animal cell Prokaryotic cell Animal cell Prokaryotic cell A  ×     B ×    ×  C  × ×    D    ×  × 6 (c) Explain why it is possible to see the detailed structure of a prokaryotic cell with an electron microscope but not with a light microscope. (2) .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... .................................................................................................................................................................................................................................................................................... (Total for Question 2 = 10 marks)