【单选题】A couple has a female child with Tay Sachs disease, and three unaffected children. Neither parent nor any of the four biological grandparents of the affected child has had this disease. The most likel...
A.
autosomal dominant
B.
autosomal recessive
C.
sex-linked recessive
D.
sex-linked dominant
E.
cannot make a reasonable guess from this information
【简答题】Human cells have twenty-three pairs of chromosomes. One member of each pair is ________________ from the female parent, and the other member comes from the male parent. Two chromosomes that carry gene...