cell: the cell is the smallest structural and functioning unit of an organism
sex-linked disorders: a trait in which a gene is located on a sex chromosome
selective breeding: two parents with particular characteristics are chosen to breed together to get a more desirable specimen
meiosis: a type of cell division that causes four daughter cells each with half the number of chromosomes
mitosis: a type of cell division that causes two daughter cells to have the same number and kind of chromosomes as the parent nucleus
