<em>They differ from both parents and also from each other. This occurs through a number of mechanisms, including crossing-over, the independent assortment of chromosomes during anaphase I, and random fertilization. When homologous chromosomes form pairs during prophase I of meiosis I, crossing-over can occur</em>
A chromosome is made up two Identical Sister Chromatids. And each sister chromatids are joined at the centromere. A copy of each chromosome is inherited from a male parent and a female parent and this explains the characteristic traits possessed by their offspring (such as facial features reminiscent of the parents).