15. Interpret Graphs What can you infer about the relationship between the age of the mother and the incidence of Down syndrome?

    dd

14.3 Studying the Human Genome

Understand Key Concepts

16. The human genome consists of approximately how many DNA base pairs?

    1. 30,000

    2. 3,000,000

    3. 300,000,000

    4. 3,000,000,000

17. The fraction of the human genome that actually codes for proteins is about

    1. 2%.

    2. 20%.

    3. 98%.

    4. 100%.

18. Cutting DNA into small pieces that can be sequenced is accomplished by

    1. restriction enzymes.

    2. DNA polymerase.

    3. gel electrophoresis.

    4. RNA polymerase.

19. If you sequence short pieces of DNA and then use a computer to find overlapping sequences that map to a much longer DNA fragment, you are using

    1. genomics.

    2. hapmaps.

    3. shotgun sequencing.

    4. open reading frame analysis.

20. Describe the tools and processes that scientists use to manipulate human DNA.

21. Explain why restriction enzymes are useful tools in sequencing DNA.



solve the CHAPTER MYSTERY

THE CROOKED CELL

When Ava inquired about her family's medical history, she found out that Uncle Eli's mother (Ava's grandmother) also had sickle cell disease, but Uncle Eli's father did not. One of her uncle's four children also had the disease. However, Ava's father, who is Eli's only sibling, did not have sickle cell disease, nor did Ava's mother. Ava's two siblings showed no signs of the disease, either.

1. Apply Concepts In general, what pattern of heredity does the sickle cell trait follow? Cite evidence from the chapter and its clues to support your conclusion.

2. Draw Conclusions Based on your answer to question 1, what can you conclude about the inheritance of sickle cell disease in Ava's family? What might be Ava's chances of being a carrier of the sickle cell trait?

3. Classify What kind of medical test could Ava request that would help determine whether or not she has the sickle cell trait? Explain your answer.

4. Infer The restriction enzyme Mst II, which cuts normal DNA at a particular site, will not recognize (and, therefore, will not cut) DNA that contains the sickle cell mutation. If Uncle Eli's DNA is cut with Mst II, will the restriction fragments be identical to those from his brother, Ava's father? Explain.

5. Focus on the Which technique(s) that you have read about in this chapter could be used to perform the kind of test described in question 4? Which technique could be used to analyze the results?



---

End ofPage 413

Table of Contents