Question

Frank has Klinefelter syndrome (47, XXY). His mother has normal skin, but his father has anhidrotic ectodermal dysplasia, an X-inked condition where the skin does not contain sweat glands. Frank has patches of normal skin and patches of skin without sweat glands. Complete the sentences. Some answers may be used more than once or not at all. Frank received the mutant chromosome from his. Nondisjunction occurred in his during the meiotic division. first, mother, father, second

Answer 1

Frank father has skin without sweat glands. where his mother has normal skin.So his father is also affected with a disorder and supposed to be mutant. Frank would have received the mutant chromosome from his father.

Nondisjunction would have occurred at meiosis I. Because, the chromosomes separate(and not chromatids) at that stage.while separation, both XY chromosomes would have gone into a single cell.So during meiosis II when sperm with XY chromosome fuses with Egg with X chromosome the daughter cell would have an XXY genotype which is klinefelter syndrome.

Answer 2

Answer:

Frank recieved the mutant chromosome from his Father

Nondisjunction occured in his Father during the first meiotic division.

Explanation:

As we can see in the question above, Frank's father has anhydrotic ectodermal dysplasia. Which is a hereditary genetic mutation that causes abnormalities in the skin, nails, hair and even teeth.

Frank has an anomaly in his skin which is the presence of spots that do not have sweat glands. As this mutation is passed from father to son, we can see that Frank inherited the mutant gene, for this anomaly, from his father.

Frank inherited this gene during the cell division process, in his father's organism. This cell division occurred during the formation of gametes (meiosis), precisely during meiosis I, where there is a reduction in the number of chromosomes to form the gametes.