13 Flashcards
Meischer
Nuclein
Griffith
Transformation
Avery, MacLeod, McCarty
Transformation
Hershey and Chase
Blender experiment
Chargaff
There are as mnay As as Ts and as many Cs as Gs
Base
Sugar
Nucleosides
Base
Sugar
Phosphatee
Nucleotides
What direction do nucleotides go?
5’ to 3’
How are the nucleotides numbered?
Base: numbers
Sugar: number ‘ (prime)
What is attached to 1’?
The base
What is attatched to the 5’?
Deoxyphosphate
What is attatched to the 3’?
A hydroxyl group
What is significant about 2’?
2’ is either oxygenated or deoxygenated. If there is no oxygen, it is deoxyribose and is for DNA. If there is an oxygen, then it is ribose and is for RNA
Are purines or pyrimidines bigger?
purines are larger
A and G
purines
C, U, and T
pyrimidines
How any hydrogen bonds to AT and GC make?
AT = 2
CG = 3
Where does DNA replication begin?
oriC
What enzyme performs most of the DNA synthesis during replication?
DNA plymerase III
After two round of replication in light nitrogen, Meselson and Stahl observed what forms of DNA?
Intermediate and light
After one round of replication in light nitrogen, Meselson and Stahl observed what forms of DNA?
Intermediate
After three rounds of replication in light nitrogen, Meselson and Stahl observed what forms of DNA?
Intermediate and light (more light than intermediate)
Genome
the complete DNA sequence
Genotype
specific DNA sequence
Phenotype
Appearance/behavior
Prokaryotes are ____ and ____ (mostly)
circulat and haploid
positive supercoiles, ___ winding
over winding
negative supercoils, ___ winding
under winding (easier to open)
Loader places ___ at each end of origin
helicase
___ ____ needs a free 3’OH
DNA polymerase
___ begins replication
Primase
____ strand follows helicase
leading
Gaps filled in by DNA Plymerase ____
DNA polymerase I
___ seals nicks
ligase
DNA polymerase __ is involved with repair
DNA polymerase II
____ are actually stationary
replisomes
Extrachromosomal pieces of DNA
plasmids
____ plasmids have one or two copies per cell
low-copy-number plasmids
___ plasmids have up to 500 copies per cell.
high-copy-number plasmids
Low-copy-number plasmid example
f plasmid of e. coli
pbr22
Plasid replication stating at nick bound by RepA protein
unidirectional
Plasmid gene examples
- antibiotic resistance
- encoding poteins to metabolize rare food sources
- Virulence genes to allow pathogenesis
- allow symbiosis