Translation and Central Dogma Vocabulary Flashcards

A set of vocabulary flashcards covering the key terms, mechanisms, and stages of translation based on lecture notes.

Central Dogma

The framework describing the flow of genetic information from DNA (gene for a protein), which is transcribed into an mRNA sequence, to protein primary structure, which is translated from the mRNA sequence.

Codon

A set of 3 RNA nucleotides in mRNA that determines a specific amino acid in a polypeptide.

Redundant (Degenerate) Genetic Code

The characteristic of the genetic code in which multiple different codons can specify the same amino acid.

Unambiguous Genetic Code

The property of the genetic code where a specific codon codes for one, and only one, amino acid.

"Five to three, N to C" Rule

The directional rule stating that mRNA is read in the $5'$ to $3'$ direction during translation, and polypeptide chains are synthesized from the N-terminus ($\text{NH}_2$ end) to the C-terminus ($\text{COOH}$ end).

Start Codon

The specific AUG codon in an mRNA molecule where the ribosome begins translation.

Stop Codon

A codon in mRNA that signals the endpoint of translation because it is recognized by a release factor rather than a tRNA.

Initiation (Translation)

The first stage of translation in which the small subunit of the ribosome attaches to the $5'$ end of mRNA, scans for the first AUG start codon, and is joined by the large ribosomal subunit.

Elongation (Translation)

The stage of translation where tRNAs bring amino acids to the ribosome based on complementary codon-anticodon pairing, and peptide bonds are formed to extend the growing polypeptide chain.

Termination (Translation)

The final stage of translation where a release factor binds to a STOP codon, triggering the release of the completed polypeptide and the dissociation of the ribosomal subunits.

Transfer RNA (tRNA)

An adapter molecule that matches mRNA codons with their corresponding amino acids using a complementary anticodon sequence.

Anticodon

A three-base sequence located at the bottom of a tRNA molecule that base-pairs with a matching codon on the mRNA.

A Site (Amino Acid Site)

The ribosomal site where a tRNA complementary to the incoming mRNA codon binds during the elongation phase of translation.

P Site (Peptide Site)

The ribosomal site that holds the tRNA attached to the growing polypeptide chain.

E Site (Exit Site)

The site on the ribosome from which empty tRNAs exit during translation.

Release Factor

A protein that binds to the STOP codon during termination, causing the final amino acid to detach from the tRNA and the ribosomal subunits to fall apart.