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.
Severe defects in chromosomes block progression through the cell cycle, and can lead to cell suicide, or apoptosis. In addition, cells have a finite lifespan, and at some point are no longer able to divide. Cancers are diseases in which there is a defect in the regulation of the cell cycle.