Figure 13.1 - Figure 13.2

question 5

Multiple Choice

Figure 13.1
- Figure 13.2
In an experiment, DNA is allowed to replicate in an environment with all necessary enzymes, dATP, dCTP, dGTP, and radioactively labeled dTTP (3H thymidine) . After several minutes, the DNA is switched to nonradioactive medium and is then viewed by electron microscopy and autoradiography. Figure 13.2 represents the results. It shows a replication bubble, and the dots represent radioactive material. Which of the following is the most likely interpretation of the results?

• A) There are two replication forks going in opposite directions.
• B) Thymidine is being added only where the DNA strands are farthest apart.
• C) Thymidine is being added only at the very beginning of replication.
• D) Replication proceeds in one direction only.

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Definitions:

Japanese-American Internment

The forced relocation and incarceration in camps of about 120,000 Japanese Americans and Japanese residents living on the Pacific Coast of the United States during World War II by order of the U.S. government.

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A secret U.S. government research project during World War II that developed the first nuclear weapons.

Bald Tires

Tires that have lost their tread, reducing traction and increasing the risk of accidents, especially in wet conditions.

Wartime Sacrifice

The act of giving up something valued for the sake of something else considered to be of more importance or worth, particularly in the context of individuals or societies during war.