Isotonic, Hypotonic, and Hypertonic Solutions. Water moves readily across cell membranes through special protein-lined channels, and if the total concentration of all dissolved solutes is not equal on both sides, there will be net movement of water molecules into or out of the cell.
Crossing over – often, the sister homologous chromosomes of a cell exchange genetic material through recombination of genes.
Independent assortment/random fertilization – there are numerous variety of ways that the chromosomes of the gametes can combine, after meiosis, through fertilization to form a zygote
Mutation – on rare occasion, there is a slight and random change in the genes of a gametic cell caused by environmental factors.
