Practise explaining semi-conservative DNA replication, polymerase action, and Meselson-Stahl evidence from density-gradient bands.
When an organism grows or increases in number, cell division takes place.
When a cell is preparing to divide, DNA synthesis takes place. Explain how two identical molecules of DNA are produced.
The Voronoi diagram shows the proportions of molecules in a bacterial cell. The area of each labelled part of the square is proportional to the percentage of the dry mass of that molecule. The shape of each part has no meaning.
The proportions of these molecules change as a bacterial cell prepares to divide, as it divides into two new bacterial cells and as each new bacterial cell grows. Discuss how the appearance of this Voronoi diagram might change: - as a bacterial cell prepares to divide - in one of the new bacterial cells produced - as one new bacterial cell increases in size. Give reasons for these changes to support your answer.