Protein synthesis (2.6)

Question 1

Describe the process of transcription

Answer 1

-A section of DNA uncoils and hydrogen bonds are broken between the polynucleotide strands seperating them. Only one of the strands is then used as a template.
- RNA nucleotides bind to the DNA nucleotide bases via complementary base pairing, with uracil (RNA) pairing with adenine (DNA).
- An enzyme called RNA polymerase joins the RNA nucleotides together to form a strand of messenger RNA. These bonds between RNA nucleotides are called phosphodiester bonds.
-The mRNA leaves the nucleus through a nuclear pore
-The strands of DNA in the nucleus will reform and the hydrogen bonds will reform betweem the bases.

Question 2

Describe the process of translation.

Answer 2

-The process of translation occurs in the ribosomes, in which the mRNA binds to the ribsomes in order for the process to start.
- The ribosomes read a codon from the mRNA (3 bases on the mRNA that code for specific complementary bases) and call for the right tRNA.
- Here the tRNA, which has three complementary ends for the codon (anticodon) will bind to the mRNA starting the amino acid chain (remember that specific anticodons code for a certain amino acid).
-When a second tRNA binds to the next codon in the mRNA, a condensation reaction will occur between the amino acids creating a peptide bond.
-The first tRNA then leaves the mRNA and the ribsome moves up the mRNA chain for another third tRNA to join and drop off its amino acid.

Question 3

Define the term codon and anticodon.

Answer 3

CODON = A codon is a three-nucleotide or triplet sequence found on mRNA that codes for a certain amino acid during translation.
ANTICODON = The anticodon is a three-nucleotide sequence found on tRNA that binds to the corresponding mRNA sequence.