What are the chances of the second child being blue-eyed | Homework Help

1. Brown eyes are dominant over blue. What are the chances that the first child of a marriage of two hybrid (heterozygous) brown-eyed parents will be blue-eyed? What are the chances of the second child being blue-eyed?

2. In humans, color-blindness is recessive and sex-linked. A man of normal vision marries a woman of normal vision, whose mother was color-blind. What kind of vision would be expected in their offspring? What kind of vision did the wife’s father have?

3. In snapdragons flower color is inherited via incomplete dominance. What would the expected colors be (in percentages) if a red snapdragon is crossed with a white snapdragon?

4. In humans, blood types A and B are codominant with type O being recessive. List the blood types of the offspring of a father with blood type AB and a mother with type O.

5. An individual that does not have the sickling gene mates with an individual with one copy of it (sickle cell trait). What percent of their offspring would have sickle cell disease? and sickle cell trait?

6. An Rh + woman (her mother is Rh-) marries and Rh- man. What percent of their children would be expected to be Rh + and Rh-? Remember Rh+ (RR and Rr) is dominant over Rh- (rr).

7. Two carriers of cystic fibrosis mate, what percentage of their offspring would have cystic fibrosis?

8. A brown eyed male (who’s mother has blue eyes) marries a blue eyed female. What color eyes would be expected in their offspring?

9. A woman is blood type A and has a child with blood type O. She names John Doe as the father of her child. What blood type would exclude him as the father?

10. In humans, migraine is due to a dominant gene (M). A normal-visioned woman who has never suffered from migraines takes her daughter to a doctor for an examination. In the course of the examination, the doctor discovers that the girl is color-blind and suffers from migraines. What does the doctor automatically know about the father? (Remember that color-blindness is recessive and sex-linked).