2: The Genetic Material Flashcards
What experiment did Griffith perform?
The transformation experiment. He used S, virulent and R, non-virulent bacteria to discover the transforming principle.
What are the 4 requirements for genetic material?
- Relatively stable
- Replicate accurately
- Capable of change
- Able to be packaged
What did avery, mcleod, and mccarty find?
DNA is the transforming agent.
The hershy-chase experiment
Used E. Coli infected with bacteriophage t2
How was RNA discovered as viral genetic material
In the tobacco mosaic virus
What are the 3 components of a nucleotide?
- A pentose (5-carbon) sugar
- Nitrogenous base
- Phosphate group
What is the difference between ribose and deoxyribose?
Deoxyribose doesn’t have a 2’ hydroxyl group
What is a nucleoside?
The sugar-base
What is Chargaff’s rule?
The amount of purine is always equal to the amount of pyrimidine.
Rosalind franklin’s x-ray diffraction images of dna showed….
A helical structure with regularities at 0.34 nm along axis of the molecule
There are ____ base pairs per turn of the helix.
10
The dna helix is ______-handed.
right
The dna helix has _____ and _____ grooves that are important for _______ ________.
Major; minor; protein binding
A-DNA
Right-handed, 10.9 per turn, short and wide
B-DNA
Normal dna
Z-DNA
Left-handed, 12 bp, elongated and thin
How many bp in humans?
~3 billion
A ______ in supercoiled dna will allow it to return to a relaxes dna circle.
nick
What is the purpose of topoisomerase?
It supercoils dna
What is the c-value?
The total amount of dna in the haploid chromosome of a species
What is the c-value paradox?
The structural complexity and the c-value of an organism are not related
The dna-protein complex is called _______ and it is highly conserved in all ________.
Chromatin; eukaryotes
The 5 types of histones
- H1
- H2A
- H2B
- H3
- H4
How much dna relative to histones do chromosomes have?
An equal weight of both
