Unit 4 History of DNA

Question 1

1. Phoebus Levene 1919

Answer 1

Discovered DNA = chains of nucleotide

nucleotide = same repeating pattern
like a cycle of base, sugar, and phosphate groups

he needs to RTA (recolonize the alpha[glucose]

Question 2

2. Frederick Griffith 1928

Answer 2

Found
-organisma can acquire new properties from enviroment and others
-non heritable exchange of genetic info is possible
-transforming principal

Experiment on pneumonia bacteria in mice

S-strain (bad)

R-strain (ok)

Question 3

4. Avery, McLeod and McCarty, 1944

Answer 3

Found: DNA=hereditary material in cells not proteins

more pneumonia bacteria

R-strand (ok) was mixed with enzymes that destroy protiens, RNA, and DNA

all types resulte din the s-strain(bad) EXCEPT the one that destroyed DNA

Question 4

3. Joachim Hammerling 1930

Answer 4

Found hereditary material is in the **nucleus*

Experiement: single cell organism, cut stem=head still grow

cut nucleus= no grow