DNA replication and protein synthesis Flashcards
What did T.H. Morgan group find by studying fruit flies?
That genes are located on chromosomes
What became the two candidates for the genetic material ?
DNA
Protein
What did Frederick Griffin discover in 1928?
He discovered the genetic role of DNA and observed the principle of transformation
What did Avery, McCarty and McLeod find?
That transformation only occurred when DNA remained active (so proteins and RNA were not the transforming agent)
What did Hershey and Chase show in 1952?
That DNA is the genetic material of a phage called T2
What did Chargaff report in 1950?
That in any species, A =T and C = G
That the ration of A+T vs C+G varies among species
Why is DNA replicated?
For growth
For reproduction
What is the error rate of DNA replication?
1 error per 10 billion nucleotides
What type of replication does DNA undergo?
Semiconservative replication
What is the role of helicase?
It untwists the double helix at the replication fork.
What is the role of the single-strand binding protein (SSBP) ?
It bind to and stabilizes single stranded DNA until it is used as a template
What is the role of topoisomerase?
it corrects overwinding ahead of the replication fork by breaking, swiveling anfd rejoining DNA strands
What is the difference between Type I and Type II topoisomerase?
Type I cuts only one DNA strand, whereas Type II cuts both strands.
What is the role of primase?
It reads the parental DNA (3’ to 5’)
It synthesizes the primer (5’ to 3’)
What is the role of DNA polymerase?
It adds nucleotides to the 3’ end of the primer/ growing strand
It catalyses the elongation of new DNA
