Protein Synthesis and Genetic Code Quiz

Protein Synthesis Overview

• Translation is the process where the genetic code in mRNA is decoded to produce a specific sequence of amino acids.
• A polypeptide chain forms until a ribosome encounters a stop codon on the mRNA strand, leading to its release and completion of protein synthesis.

Genetic Code and Codons

• mRNA's instructions for building polypeptides are organized in triplet sequences known as codons.
• Each codon in the mRNA corresponds to a specific amino acid, establishing the framework of the genetic code.

Using the Genetic Code Chart

• The genetic code chart is a wheel where mRNA codons are read from the inside out.
• Start in the center with one of the four big letters for the first letter of the codon.
• Move to the second ring to find the second letter, and then to the smallest set in the third ring for the third letter.
• The outermost ring displays the name of the corresponding amino acid.

Translation Process Steps

• Initially, mRNA binds to a ribosome to begin translation.
• tRNA molecules carrying specific amino acids approach the ribosome to form an initiation complex.
• The anticodon on tRNA pairs with the start codon on mRNA, typically AUG, which codes for methionine and signals the start of protein synthesis.
• The ribosome then moves along the mRNA to the next codon, allowing a new tRNA molecule to pair with it.
• As the first two amino acids are brought together, an enzyme catalyzes the formation of a peptide bond between them.

Codon and Anticodon

• A codon is a three-nucleotide sequence on mRNA that encodes a specific amino acid.
• An anticodon is a complementary three-nucleotide sequence on tRNA that pairs with the corresponding mRNA codon, ensuring the correct amino acid is added.