Bio 13.1 Quiz

Frederic Griffith discovered transformation in his experiments on mice and Pneumococcus bacteria. He injected the mice with combinations of harmless, R-strain bacteria and disease-causing S-strain bacteria. Which combination of bacteria killed the mice and showed that transformation occurred?

• heat-killed R-strain and live S-strain

• heat-killed S-strain and live R-strain

• heat-killed bacteria of both strains

• live bacteria of both strains

To learn more about Griffith’s experiment, scientists extracted a mixture of various molecules from the heat-killed bacteria. They found that ​ (a)   no longer occurred when they treated the mixture with enzymes that ​ (b)   DNA. This experiment supports the hypothesis that ​ (c)   is the genetic material.

• Proteins

• RNA
• transformation
• DNA
• destroyed
• copied
• transcription

Which statements describe a bacteriophage? Select all that apply.

• It is a type of virus that infects bacteria.

• It is a type of bacteria that infects viruses.

• It is a virus consisting of a protein coat and a DNA core.

• It is a bacterial strain consisting of protein and a DNA core.

What was the purpose of marking the bacteriophages with phosphorus-32 and sulfur-35?

• to track the movements of DNA and sugars

• to track the movements of DNA and proteins

• to remove DNA and sugars from the bacteriophages

• to combine DNA and proteins into a single molecule

What are three tasks that DNA must be able to perform in all organisms?

• It must store genetic information.

• It must discard foreign genes.

• It must instruct cells to produce needed molecules.

• It must copy itself.

• It must move to locations throughout the cell.

When does transformation occur?

• when an organism receives foreign RNA that is transformed into DNA

• when DNA is transformed into RNA

• when bacteria are killed with heat

• when a cell receives foreign DNA that is expressed as a new characteristic