Ch 14, L 1, The Nature of the Genetic Material

What is a virus that infects bacteria called?

• bacteriophage

• infectious virus

• transformation

• gene change

Who discovered that bacteria could be changed by the process of transformation?

• Griffith

• Hershey & Chase

• Avery

• Franklin

By using radioactive isotopes, Hershey and Chase were able to conclude that __ is/are the carrier(s) of genetic information.

• DNA
• Proteins
• Carbohydrates
• Lipids

S-strain bacteria

• caused pneumonia
• had a smooth appearance
• was covered by a mucus-like coat
• all of these

Griffith discovered

• that DNA was the genetic material
• that R-strain had transformed into S-strain
• that x-rays can take pictures of DNA
• that mice aren't very good for genetic studies

Oswald Avery discovered

• DNA was the transforming principle
• that there is more phosphorus in DNA than in protein
• how viruses work
• the structure of DNA

When a mouse was injected with living S bacteria, the mouse ___________

• Lived
• Died

When a mouse was injected with BOTH heat-killed S bacteria AND living R bacteria, the mouse ___________

• Died
• Lived

Why did Hershey and Chase chose to study bacteriophages?

• They are only made of protein and DNA
• They are easy to keep alive in the lab
• It would help them cure cancer
• They are made of only DNA

Hershey and Chase wanted to find out which part of a bacteriophage ____________________.

• entered the bacteria cell
• was made of nitrogen
• was radioactive
• contained carbon