Louisiana State University

BIOL 1201

Chapter 15

1)What can we observe in order to visualize Mendel’s Law of Segregation?

 

 

2. What name is given to the most common phenotype in a natural population?

 

 

3. A white-eyed female Drosophila is crossed with a red-eyed male Drosophila. Which

statement below correctly describes the results?

 

 

4. In humans, what determines the sex of offspring and why?

 

 

5. In general, the frequency with which crossing over occurs between two linked genes depends on what?

 

 

6. Which of the following results in a situation in which the chromosome number is either 2n+1 or 2n-1?

 

 

7. What results if a fragment of a chromosome breaks off and then reattaches to the original chromosome at the same place but in the reverse direction?

 

 

8. What phenomenon occurs when a particular allele will either be expressed or silenced,

depending on whether it is inherited from a male or a female?

 

 

9. How are human mitochondria inherited?

 

 

10. Which of the following is true of an X-linked gene, but not of a Y-linked gene?

 

 

11. Cinnabar eyes is a sex-linked recessive characteristic in fruit flies. If a female having

cinnabar eyes is crossed with a wild-type male, what percentage of the F₁ males will have cinnabar eyes?

 

 

 

12. Recombination between linked genes comes about for what reason?
13. When Thomas Hunt Morgan crossed his red-eyed F₁ generation files to each other, the F₂ generation included both red- and white-eyed flies. Remarkably, all the white-eyed flies were male. What was the explanation for this result?
14. A woman is found to have 47 chromosomes, including three X chromosomes. Which of the following describes her expected phenotype?