THE ROLE OF DNA AND BACTERIA

DO NOW• 4 minutes and 27 seconds to write down 5 things from last class

• Do NOT use your notes

HOMEWORK• Review Worksheet due today

• The Role of DNA

HOMEWORK DUE TOMORROW• Read pg. 344-348 The Structure of DNA

• Answer Questions 1 & 2 on pg. 348

REVIEW• Griffith’s Experiments

• Mice

• What were his experiments?

• What were his conclusions?

REVIEW• Oswald Avery

• What did he base his experiments off?

• What were his conclusions?

BACTERIAL VIRUSES• Bacteriophage is a virus that infects bacteria

• Bacteriophage attaches to the bacterial cell and injects genetic information

• Viral gene now produces more bacteriophages and destroys the bacterial cell

• Are these good?

• The Food and Drug Administration FDA has approved the use of some bacteriophages to use on food

• Used to treat ready to eat meat and poultry dishes

HERSHEY-CHASE EXPERIMENT• Experiments thus far had looked into the genetic makeup of viruses and bacteria, but

what part of the bacteriophage enters the bacterial cell?

• Viruses made up of protein coat and DNA

• Which part enters the cell?

• Grew viruses with radioactive phosphorus (P) and radioactive sulfur (S)

• Protein contains no phosphorus, DNA contains no sulfur

• After mixing, found the radioactive phosphorus inside the bacterial cells

ROLE OF DNA• Store Information

• Must carry the information to make things the way they are

• Ex: Eye color, hair color, flower color

• Copy Information

• Before cell division, must copy every gene

• Transmitting Information

• Mendel’s work showed that genes are transmitted from one generation to the next

• Loss of DNA probably means a loss of valuable genetic information

BILL NYE – GENES!• http://www.youtube.com/watch?v=OZIQTMHmWmg

HOMEWORK DUE TOMORROW• Read pg. 344-348 The Structure of DNA

• Answer Questions 1 & 2 on pg. 348