KA3- Transcription Flashcards
What is transcription?
The synthesis of mRNA from a section of DNA that codes for a gene
What is RNA polymerase responsible for?
Transcription
Where does transcription of DNA happen?
In the nucleus
Does RNA polymerase need primers?
No
What happens as RNA polymerase moves alone DNA?
It synthesises a primary transcript of RNA from RNA nucleotides by complementary base pairing
How does RNA polymerase synthesise?
Complementary base pairing
What happens to the double helix as RNA polymerase moves along DNA?
It unwinds and unzips and it has its hydrogen bonds broken
What happens to the DNA when it’s unzipped?
It’s strands separate and its bases are exposed
What do free RNA nucleotides pair with?
Complementary DNA nucleotides
What can RNA polymerase only add nucleotides to?
The 3’ end of the growing mRNA molecule
How is the new sugar-phosphate backbone of mRNA formed?
RNA polymerase joining the RNA nucleotides together with strong covalent chemical bonds
How does RNA polymerase join RNA nucleotides together?
Strong covalent chemical bonds
What type of replication is the leading strand?
Continuous
What type of replication is the lagging strand?
Discontinuous
When does transcription stop?
When RNA polymerase reaches a terminator sequence
