Each time DNA replication takes place, a dividing cell is at risk of losing genetic material. On Fig. 1.1, add a label line and the letter G to show where on the chromosome there is a region that helps prevent genes from being lost.
The chromosome in Fig. 1.1 is made up of one long DNA molecule together with histone proteins. Name one stage of mitosis in which a chromosome would have the same overall structure as the one shown in Fig. 1.1.
Name the stage in the mitotic cell cycle when the cytoplasm and the cell divide to form two genetically identical daughter cells.
Cell cycle control can be influenced by extracellular chemical messengers that bind to proteins and glycoproteins in the cell surface membrane. The overall process is called cell signalling. State the term for the proteins and glycoproteins that act in this way.