Hemophilia is a sex-linked genetic disorder that inhibits the blood's ability to clot properly. The image shows how
hemophilia passes on from parent to child. Study the image and then answer the questions that follow.
X-Linked Inheritance Hemophilia
XY
affected
father
unaffected
mother
XY
XX
unaffected sons daughters (carriers)
XX
XY
unaffected
father
sons (50%)
Ba
XY
mother
(carrier)
XX
daughters (50%)
XX

Is the gene that causes hemophilia recessive or dominant? Use the image to explain your reasoning.