Protein Synthesis (Needs finishing)

Question 1

Transcription Process

Answer 1

DNA helicase hydrolyses H bonds in specific region of DNA to expose nucleotide bases
Complementary free RNA nucleotides form H bonds on the template strand
RNA polymerase forms phosphodiester bonds between nucleotides
When a stop triplet code is reached, RNA strand detaches to form pre-mRNA strand

Question 2

Splicing process

Answer 2

Introns are removed from pre-mRNA to form mRNA

Does not occur in prokaryotic cells, do not have introns

Question 3

Why does splicing occur

Answer 3

Introns are non coding so must be removed
Exons are coding so are left on the mRNA strand

Question 4

Translation Process

Answer 4

mRNA enter ribosome
tRNA molecule with complementary anticodon moves to complementary codon on mRNA
This carries a specific amino acid to the mRNA molecule
tRNA with complementary anticodon to the next codon pairs and brings specific amino acid to mRNA
ATP and an enzyme help form condensation reaction between amino acids, forming peptide bond
This process repeats until the stop codon is reached
mRNA and tRNA molecule all separate and polypeptide is released into cell