Have you ever thought why your hair is a certain color or your eyes? Each gene in our DNA determines or in some way affects something in our body. This is true for humans and all other living things. DNA is composed of tons of different genes. Each gene controls a trait that is expressed in the body of the organism. Human are thought to have twenty-five thousand genes. Genes undergo changes over the life of the organism they are in. In many cases genes can be altered naturally and in some cases can be altered by their environment. Genetics is the science of understanding how characteristics are transferred from a parent to their young.
This series of worksheets keys in on the prediction of hereditary trait transfer. They start with simple Punnett Squares and move to detecting complex Dihybrid traits.