3.10 Protein Synthesis Flashcards
What is transcription
Base sequences of genes are coped and transported to the site of protein synthesis by rna as dna is too big to leave nucleus
What first happens in transcription
Section of dna unwinds by dna helicase by breaking the hydrogen bonds
What strand of dna contains the code for the protein to be synthesised
Sense strand
Runs from 5’ to 3’ m
What is the antisense strand
Other strand that doesn’t code for a protein but is a complementary copy of the sense strand and acts as the template strand during transcription
What happens when the dna strand is unwinded
Free rna nucleotides will base pair with the complemtaty bases on the antisense strand
Phosphodiester bonds are formed between the rna nucleotides by rna polymerase
What is the completed short strand of rna called in transcription
Messenger rna
What ribosomal rna
Maintains the structural stability of the Protein synthesis sequence and catalysed the reaction
What happens in translation
When mRNA has left the nucleus
mRNA binds to specific site in the small subunit of a ribosome
Ribosome holds mRNA in position while it’s decoded into a sequence of amino acids
What is transfer rna
Composed of a strand of rna folded in such a way that three bases called the anticodon are at on end of the molecule
It carries an amino acid that corresponds to each codon
What is a anticodon
3 bases at one of end the tRNA molecule
It binds to a complementary codon on the mRNA strand
How does translation create the primary structure of the protein
mRNA binds to small subunit of the ribosome at it’s start codon
Trna with complementary anticodon binds to mRNA start codon
This process repeats and the amino acids are brought together in the correct sequence - forms a peptide bond
How is a protein created by teh amino acids in translation
As the amino acids join together they fold into secondary and tertiary structures
