Dna Transcription Flashcards
Define transcription
Changing from one language to another
3 steps of transcription
Plans are made and stored,
Copies of original plans are made
It is then constructed
Transcription with DNA and rna definition
Making rna out of DNA templates
How is DNA made
Transcription factors bind to a tata box, the rna polymerase bonds, transcription factors join and atp allows energy to start transcription, once transcription is complete a new rna strand is released.
What 3 steps does transcription involve
Initiation, elongation and termination
What happens in the initiation step
Initiation factors bind onto tata box, and rna polymerase finds starting point with help if initiation factors
What happens in elongation step
Rna polymerase reads the DNA antisense strand, complementary mRNA nucleotides are added to growing mRNA strand
What happens in termination step
Once the rna polymerase has read the triplet a stop codon is read and it will disengage, the mrna can pass through the nuclear pore to the ribosomes,
Ban will zip up
How does mrna become more usable
Undergoing 3 modifications
What is the first modification an mrna undergoes
5’ cap is added to start of mRNA
Second modification mrna undergoes
Introns are removed. Small lengths of rna within the mrna are snipped out.
What is a spliceosome
A group of endonucleases that snip out introns from the rna
What is the third modification mrna undergoes
Poly a tail is added.
How is poly a tail added to mRNA
Poly a polymerase
What is translation
The synthesis of a protein from a mrna template
