Download Molecular Genetics

Molecular Genetics
DNA
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Key Concepts
What did scientists discover about the relationship between genes and
DNA?
What is the overall structure of the DNA molecule?
Write who the following researchers are with their discoveries:
1. Concluded that the genetic material of a bacteriophage is DNA.
2. Concluded that DNA was the factor that caused one bacterium to
transform into another.
3. Concluded that bacteria could be transformed from harmless to
disease-causing by an unknown factor.
4. Discovered the structure of DNA.
Griffith and Transformation
1. What did Fredrick Griffith want to learn about bacteria?
2. Circle the letter of each sentence that is true about Griffith’s
experiment.
a. Mice injected with nonencapsulated bacteria died.
b. Mice injected with encapsulated bacteria died.
c. Mice injected with heat-killed bacteria from nonencapsulated
bacteria died.
d. Mice injected with a mixture of bacteria from heat-killed
encapsulated bacteria and nonencapsulated bacteria died.
3. What is transformation?
4. What hypothesis did Griffith form from the results of his experiments?
Avery and DNA
5. Briefly describe how Avery and his group determined which molecule
was most important for transformation
The Hershey-Chase Experiment
6. What happens when a bacteriophage infects a bacterial cell?
7. How would Hershey and Chase learn whether genes were made of
protein or DNA?
8. What did Hershey and Chase observe?
The Components and Structure of DNA
9. What is the makeup of a nucleotide?
10. Adenine, guanine, cytosine, and thymine are four kinds of
____________ bases in DNA.
11. Which of the bases are purines? Which are pyrimidines?
12. What forms the backbone of the DNA chain?
13. What is Chargaff’s rule?
14. What is the shape/structure of DNA?
15. Use Chargaff’s rule to determine the approximate percentage of
thymine in a DNA molecule, if 28% of the nucleotides in the molecule
contain adenine.
Molecular Genetics
DNA Replication
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Key Concept
What happens during DNA replication
Review Questions
1. Where is DNA located in the eukaryotic cell?
2. What structure forms as the loose DNA becomes condensed?
3. What enzymes are involved in the process of DNA replication?
4. In what direction is the new strand of DNA being formed?
5. What is meant by an antiparallel arrangement?
6. What is meant by replication being semiconservative?