DNA (T1)
DNA Structure
History
Griffith (1940s) (1940s)
proteins were the hereditary material
Hershey & Chase
DNA was the hereditary material
Chargaff (1940s)
Came up with three rules
# of Purines always = Pyrimadines
# adenine always = # thymine
# cytosine = # guanine
Franklin
used x-ray crystallography/diffraction to show that DNA had a helical structure
Watson and Crick
made a 3-D model of DNA that illustrated the double helix and the relationship between the nitrogenous bases
DNA (deoxyribonucleic acid)
At the nucleus
Double helix
Made of two strings of nucleotides
joined in the middle by hydrogen bonds
Nucleotides
Shaped like a ladder
Backbone
deoxyribose (sugar)
phosphate group
Rungs
nitrogenous base (A,C,T,G)
Purines are adenine and guanine
Pyrimadines are cytosine and thymine (both have y in them)
Storage
DNA is typically stored in cells as chromatids within the nucleus
DNA becomes a chromosome right before replication!