You flip a coin because the allele has a 1/2 - 1/2 probability of the two outcomes as is the case when a parent is heterozygous at a locus and so there is a 1/2 - 1/2 probability for each of the two alleles getting passed on to the offspring.
Every animal-like cell has two small organelles called centrioles. They are there to help the cell when it comes time to divide. They are put to work in both the process of mitosis and the process of meiosis.
