Cell division
All cells are produced by the division of other cells. Having more than one cell. organisms start their lives as a single cell. To produce a fully developed organism a series of cell divisions must occur. Each time a cell divides two daughter cells are produced.
Cell division of body cells continues in some locations in the bodies of adult organisms where stem cells are present. Plants continue to grow throughout their lives and cell division occurs in regions of growth at the shoot and root tips. In animal bodies cell division allows growth to occur and the replacement of dead or damaged cells.
Cell division has two parts:
- Division of the chromosomes in the nucleus.
- Division of the cytoplasm.
A type of cell division which produces daughter cells identical to the parent. is the division of the nucleus. The number of chromosomes within the nucleus is firstly doubled, then the chromosomes are divided between the nuclei of the two daughter cells produced by cell division.
This ensures that the diploid chromosome complement of cells is maintained. The daughter cells therefore have all the genes they need to function correctly.