Chapter 5 Flashcards
Who performed the Transforming principle Experiment
Fredrick Griffith’s- 1920’s
Take home point of the transforming principle
the S strain could permanently change or transform the nonlethal R strain into the lethal S strain
Who discovered what the transforming principle was?
Avery, Macleod, & McCarty- 1940’s
What was the transforming principle?
DNA
Who performed the blender experiment?
Hershey and Chase- 1952
What was used to prove genetic material was DNA in the blender expiriment?
Bacteriophages
What two isotopes were used in the blender experiment?
32P and 35S
Where was the radioactivity in the flask of the protein trial?
The radioactivity was in the liquid
Where was the radioactivity in the flask of the DNA trial?
in the pellet, which consisted of the bacteria
Who solved the structure of DNA?
Rosalin Franklin
What connects the DNA strands to eachother?
hydrogen bonds
What holds the individual DNA strands together?
Phosphodiester (Covalent)
Which connection is stronger, G-C or A-T?
G-C, there are 3 h bonds between them while there are only 2 between A-T
How much DNA is in a nucleus?
6 ft or 2m
what is a gene?
DNA sequence coding for protein or RNA
What is a Genome?
collection of genes
Difference between coding and non-coding DNA?
non-coding DNA doesn’t make protein
How many chromosomes do you have?
46, 23 pairs (one side of each pair from parent)
What is the charge of a histone octamer?
positive (attracts negatively charged DNA)
How many proteins total in a histone?
2 H2A + 2 H2B + 2 H3 + 2 H4 = 8
Which protein makes the histone tail?
H3
Energy used by remodeling complex?
ATP
what does the remodeling complex do?
It shifts chromatin as needed to create txn active vs non txn active
traits of euchromatin
less condensed, TXN active (gene accessible), occurs in Interphase
traits of heterochromatin
Not TXN active (less accessible), occurs in mitosis, highly condensed
Is heterochromatin and euchromatin interconvertible?
YES
Why are some x-chromosomes inactivated in females?
one of the two x-chromosomes is randomly and permanently inactivated in cells other than eggs. This is referred to as X-inactivation
What is a nucleosome?
it is DNA + Histone
Most common form of DNA?
BDNA
