Question

Please help me please

Answer 1

Answer:

Please see the answer below

Explanation:

a. The roman numerals represent the various generations in the pedigree.

    I represents first generation

   II represents the second generation

b. The half shaded square and circle representing the parents means that both of them are carriers for the trait in question. Tay-Sachs disease is an autosomal recessive inheritance, assuming the trait is represented by the allele a, the gentoypes of the parents would be Aa and Aa respectively.

c. Still on the assumption that the disease is represented by the allele a. If offpsring II4 which happens to be free of the Tay-Sachs allele marries a person that also does not carry the Tay-Sachs disease gene, the cross will be as shown below.

AA   x   AA = AA, AA, AA, and AA.

All the children would be free from the Tay-Sach's allele. That is, they will be homozygous normal.