Normal body cells have a diploid number of chromosomes, two of each chromosome.
Gametes have a haploid number. There is only one copy of each chromosome.
Cells formed by meiosis are all genetically different, because each new cell has a different combination of chromosomes.
Interphase occurs before meiosis. DNA unravels and replicates so two copies of each chromosome are in the cell.
Each copy is a chromatid. A pair are sister chromatids. Joined with a centromere.
*Chromosomes condense, become shorter and fatter.
*Homologous chromosomes pair up.