Review the definitions of the following terms with students: trait, chromosome, gene, mutation, dominant, recessive. Emphasize to students that mutations can occur in both body cells and sex cells.
Consider the following question for group discussion:
If a mutation occurs in a body cell, what effect would it have on the organism? Its offspring?
A mutation in a body cell only affects the organism that carries it. It will not be passed on to its offspring. If a mutation occurs in a sex cell, it can be passed on to the next generation and cause a change in that generation. However, most individuals who have genetic disorders have the same mutation in
body and sex cells.