To protect vulnerable 16 and 17 year olds, the offences of 'abuse of a position of trust' prohibits sexual contact between adults and children under 18 in schools, colleges and residential care.
Chromosome abnormalities usually happen as a result of an error in cell division. Meiosis is the name used to describe the cell division that the egg and sperm undergo when they are developing. Normally, meiosis causes a halving of chromosome material, so that each parent gives 23 chromosomes to a pregnancy.
Many errors can occur during cell division. In meiosis, the pairs of chromosomes are supposed to split up and go to different spots in the dividing cell; this event is called disjunction.. However, occasionally one pair doesn't divide, and the whole pair goes to one spot.