1 Hemophilia is a genetically inherited disease that causes

1. Hemophilia is a genetically inherited disease that causes the synthesis of abnormal clotting factor VIII. As a result, hemophiliacs bleed excessively from the slightest injury. The figure below is a partial pedigree for the hemophilia trait in Queen Victoria’s descendants. The pedigree indicates no history of hemophilia for either parent prior to Queen Victoria’s generation. Remember that half-shaded individuals may represent heterozygotes from an autosomal or X-linked recessive inheritance pattern.

1.     According to the figure above, which of the following assumptions about the parental generation must not be true?

Select one:

a.Neither Albert nor Queen Victoria had the gene mutation for hemophilia.

b.Albert did not have the gene mutation for hemophilia

c. Queen Victoria had two X chromosomes, one of which contains the gene mutation for hemophilia.

d. Albert was not a carrier of the hemophilia gene mutation.

2. A true-breeding pea plant with round and green seeds was crossed to a true-breeding plant with wrinkled and yellow seeds. Round and yellow seeds are the dominant traits. The F1 plants were allowed to self-fertilize. In the F₂generation, there were 152 round and yellow seeds, 101, round and green seeds, 95 wrinkled and yellow seeds and75 wrinkled and green seeds.

What is the Chi Square value?

Select one:

a. 1.75

b. 0.115

c. 125.78

d. 12.5

Solution

1. Answer - Option A is not true - Neither Albert nor Queen Victoria had the gene mutation for hemophilia.Because any one of them should be a carrier due to which their kids had the disease.

2. Answer - Option C - 125.78.

The chisquare is calculated using the formula sum of (observed - Expected )² The observed values are provided in the question and the expected value is the total number/16 and the dihybrid ratio 9:3:3:1.