Nucleotides, nucleic acids
and the genetic material
It all started with Mendel
An example of a two factor
cross
Nettie Sevens, Walter
Sutton and Edmund Wilson, working with the giant chromosomes of Brachystola
(grasshoppers) formulated the chromosomal theory of heredity.
Chromosome theory of
heredity cont.
Chromosome theory of
heredity cont.
The fly room
Slide 8
Sturdevant’s experiment
demonstrating recombination
What is the actual genetic
material, ie what is the composition of chromosomes?
Archibald Garrod
One gene one enzyme
Slide 13
Fred Griffith
Slide 15
What should have been the
definitive experiment
Avery el.al.’s Experiment
Hershey Chase blender
experiment. Okay, okay its DNA
Slide 19
DNA structure
DNA structure
"The structure of DNA
was..."
DNA structure
DNA structure
Slide 25
The structure of
nucleotides
The key to how DNA works
resides in its structure and in how it duplicates
Conservative verses
semiconservative replication
The experiment
Slide 30
Now we understand how DNA
must replicate but how does it actually happen?
Mechanism of DNA
replication
This is a simplified
view. The details...
Replication cont.
More replication.
Synthesis is always 5’ to
3’
Initiation of DNA syn at
oriC
DNA synthesis
How does RNA fit in; its
complementary to DNA
How do we know DNA makes
RNA
How do we know DNA makes
RNA