DNA replication
which model was accepted as the correct model for DNA replication
Semi-conservative
Who determine that DNA is the gentic material
Avery, Macleod, McCarty
DESCRIBE THE CENTRAL DOGMA MODEL
DNA is transcribed into mRNA and mRNA is translated into proteins
what are three types of base substitution mutation
silent, missense, nonsense
what are the two types of induced mutagens
physical and chemical
what are the 5 structural features of DNA
NUCLEOTIDE, STRAND, DOUBLE HELIX,
CHROMOSOME, GENOME
This scientist determined that the percentage of a purine matches the percentage of its complimentary pyrimidine
Erwin Chargaff
which of the following strands of DNA is read in transcription
template/ non coding strand
why does a silent mutation not alter the amino acid sequence
because of the degeneracy of the genetic code
what is the purpose of the Ames test
•Allows us to test and quantify mutagenicity of a suspected mutagen
Why is DNA replication very accurate
1.Hydrogen bonding between A and T and between G and C is more stable than mismatched combinations
2.Active site of DNA polymerase III is unlikely to form bonds if pairs are mismatched
3.DNA polymerases can proofread to remove mistakes
what hypothesis did beadle and tatum propose
one gene determines one enzyme
what are the start and stop codons
start
-AUG
Stop
-UAA
-UGA
-UAG
describe the Nuclear Excision repair
1. UVRA AND UVRB detect the mutation
2. UVRC cut the region of damaged DNA
3. UVRD remove the damaged DNA
4. Polymerase fills in the gap
What are the 3 steps involved in RNA processing
1. Splicing
2. capping
3. poly-A tail
What is the difference between the leading and lagging strand
leading strand
1. replicated continuously
2. replicated towards the replication fork
laggin strand
1. contains okazaki fragments
2. replicated away from the replication fork
Watson and Crick used the ball and stick model to determine what about the DNA?
That the structure of DNA is double helix
describe the regions in the gene that are involved in transcription
1. regulatory sequence: influence rate of transcription
2.Promoter: initiates the start of transcription
3. transcribed region: region that is converted into mRNA
4. Terminator: where transcription ends
What mutations occur to a proto-oncogene to turn it into an oncogene
1.Missense mutations
2.Gene amplifications
3.Chromosomal translocations
4.Retroviral insertions
What type of mutation occurred here
ACG UCC AGG Thr-Ser-Arg
ACG UAC AGG Thr-Tyr-Arg
Missense
What are all the proteins involved in DNA replication (IN ORDER)
DNA helicase, SSB proteins, primase, Polymerase III, DNA ligase
(what was the experiment)
genetic material (deadly capsule-secreting trait) has been transformed from the heat killed type S bacteria to the living type R bacteria which in turn made the type R bacteria lethal
Describe the process of translation
1.Initiation
–mRNA, first tRNA, and ribosomal subunits assemble
2.Elongation
–Synthesis of the protein
3.Termination
–Complex disassembles at stop codon releasing the completed polypeptide
How does a tumor suppressor gene work and provide two examples
•Typical functions
1.Maintains genome integrity by monitoring and/or repairing DNA damage
•p53
2.Inhibitors of cell division
Rb protein
when is a tumor benign, when is a tumor malignant
benign is when it is concentrated in one region,
it becomes malignant when it spreads to other areas of the body