transcription and translation

Question 1

transcription

Answer 1

• RNA plymerase binds to a site on the start of the gene
• RNA ploymerase moves along the gene seperating DNA into single strands and pairing up RNA nucleotides with complementry bases on one strand of the DNA
• Uracil pairs in a complementary fashion with adenine
• RNA polymerase forms covalent bonds between the RNA nucleotide
• RNA seperates from the DNA and the double helix reforms
• transcription stops at the end of the gene and the completed RNA molecule is released

Question 2

translation

Answer 2

• A ribsome binds to an mRNA molecule at a specific start site
• A tRNA molecule with the complementary anticodon holding its amino acid forms hydrogen bonds with the first mRNA condon
  -A second tRNA molecule binds the next codon and brings its amino acid into an adjacent site on the ribsome
  -A peptide bonds forms between the two amino acids - this is the start of the polypeptide chain
• the first tRNA molecule is released as the ribsome
• alignment of the amino acids is repeated as the ribosome moves alon the mRNA molecule