DNA as Genetic Material
In 1928 Fredrick Griffith studied rough and smooth forms of this that cause pneumonia.
what is bacteria
DNA is made of units called
nucleotides
replication means to make a
copy
viruses that infect bacteria
bacteriophages
developed base pairing rules
Erwin Chargaff
In 1944 Avery concluded that DNA must be a transforming principle or
genetic material
The four nitrogenous bases are
A= adenine
T= thymine
G= guanine
C= cytosine
Replication occurs during this stage of the cell cycle
S phase
monomers that make up DNA
nucleotides
used X-ray crystallography and assisted Watson and Crick constructing models of the double helix
Rosalind Franklin
In 1952 Hershey and Chase concluded that phages had entered the bacteria but this did not
protein
purines have ______________ rings
two
Each strand of the DNA double helix acts as a pattern or
template
structure of DNA
double helix
worked with rough and smooth bacteria to develop a "transforming principle"
Frederick Griffiths
Avery discovered that DNA contains phosphorus but this molecule contains no phosphorus
proteins
The backbone of a DNA molecule is composed of
sugar and phosphate
Place these steps of DNA replication in order:
1. two identical DNA molecules result
2. enzymes begin to unzip the double helix
3. one by one free nucleotides pair with bases exposed as the template strands unzip
2, 3, 1
T always pairs with A and G always pairs with C
1953 built models of the DNA double helix
James Watson and Francis Crick
True or False live S bacteria kept the mouse alive
False, S bacteria killed the mouse
Explain Chargaff's rule
In 1950 Erwin Chargaff discovered that the percentage amounts of adenine and thymine existed in a sample of DNA. Guanine and Cytosine bases were almost equal so A pairs with T and G pairs with C.
This enzyme helps to eliminate replication errors
DNA polymerase
enzymes that form bonds between nucleotides during replication
DNA polymerase
1952 confirmed that DNA is genetic material
Hershey and Chase