After reading the related section in the chapter, read each of the following scenarios and answer the questions about the expected phenotype in each case.

1		Jenny and Rob are going to have a baby, and they wonder whether or not it will have dimples. Having dimples is a dominant characteristic (not having dimples is recessive). Jenny has dimples and Rob does not. What are the chances that their baby will have dimples?
2		Heather and John would like to have a baby. However, they are worried because Heather has a sister that has cystic fibrosis. Although Heather does not have it, she knows that she could carry the recessive allele for it (not having cystic fibrosis is dominant). Her husband does not have any family members who have cystic fibrosis, but he could carry it too. If they both have recessive alleles for cystic fibrosis, what are the chances that their baby will have it?What would you do if you were in their situation?
3		Sara just learned that she is pregnant. She is excited, but she is worried. Her brother has hemophilia. Hemophilia is a sex-linked, recessive trait. If she carries the gene for hemophilia and she has a girl, what are the chances that it will have hemophilia? If she has a boy, what are the chances that it will have hemophilia? How would this change if her husband had hemophilia, too?