Developmental Psychology Chapter 3 Assignment Genetics
After reading chapter 3 in the text, read each of the following scenarios and answer the questions about the expected phenotype in each case.
Bethany and Hank 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). Bethany has dimples and Hank does not. What are the probabilities that their baby will have dimples?
If Bethany is homozygous:
If Bethany is heterozygous:
Jackie and Ron would like to have a baby. However, they are worried because Jackie has a sister who has cystic fibrosis. Although, Jackie does not have it, she knows that she could carry the recessive allele for it (not having cystic 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?
Rachel just found out 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 the baby will have hemophilia? If she has a boy, what are the chances that the baby will have hemophilia? How would this change if her husband has hemophilia, too?
Girl baby:
Boy baby:
Girl baby (if Dad has hemophilia):
Boy baby (if Dad has