Topic 2 - Melselson & Stahl

Question 1

Describe the experiment carried out by meselson & stahl and describe the results obtained

Answer 1

▪︎ Bacteria initially fed on medium containing N15/heavy
▪︎ DNA extracted and centrifuged after 1 cell cycle - showing a single band of heavy DNA
▪︎ Bacteria then fed on medium containing N14/light
▪︎ DNA extracted and centrifuged after 1 cell cycle - single band of medium DNA
▪︎ DNA extracted and centrifuged after 2 cell cycles in N14 - one band of medium DNA and one band of light DNA