a) Describe why teratogens are difficult to recognize.
b) Describe why a woman carrying the gene for hemophilia can generate two hemophiliac sons when she is mated to a normal male.
c) Beneath what conditions does a female acquire an X-linked recessive disorder?
d) The pedigree for Queen Victoria of England, a carrier of hemophilia A, exhibits the transmission to some of her descendants, comprising members of many royal families in Europe, like Russia and Spain, however not Germany.
Hemophilia A doesn't influence anyone in the present British royal family. Can you describe why hemophilia A has disappeared from one family and appeared in others?