Explain the process on mitosis

Mitosis is the process of cell division - in which one cell divides to form two cells that are identical to it and then also to each other. These new cells that are formed are called sister cells. The process of mitosis in important for all living organisms - its how we grow and repair and also how some organisms multiply such as bacteria

At GCSE level you need to know the basic steps of mitosis the parent cell copies its DNA so there is now two sets of identical DNA chromosomes therefore make identical copies of themselves and make an X shape -these are called sister chromatids ( remember chromosomes are just the way in which DNA is packaged within a cell that is dividing) the chromosomes line up along a line that goes across the centre of the cell each copy of the chromosome then moves apart from the other to either end or 'pole' of cell once the chromosome copies have separated fully the cell can now divide and two cells are formed

the most difficult concepts when studying mitosis are the copying of DNA and chromosomes but having a grasp of the numbers is helpful and is often an exam question We have 23 chromosomes in a normal human cells this means that when a cells begins mitosis and replicates its DNA - it will now have 46 chromosomes but once the chromosomes move apart and the cell divides this number is again halved and the new cells again have 23 chromosomes. in this way cells avoid building up necessary DNA and ensure they are identical to the original cell.