OCR GCSE Biology A · J247
Specification B5.1c · Paper 2 (Foundation), Paper 4 (Higher)
Revise: Interaction with environmentDiscontinuous variation means that values fall into distinct categories. The ABO blood groups, A, B, AB and O, provide a clear example: there is no blood group halfway between A and O. Eye colour is also commonly used as a GCSE example when eyes are grouped into categories such as brown and blue, although real eye colours include many shades.