An anticodon is the three-base sequence, paired with a specific amino acid, that a tRNA molecule brings to the corresponding codon of the mRNA during translation. The anticodon sequence is complementary to the mRNA, using base pairs in the anti-parallel direction. tRNA is read 3'-to-5', so the sequence would be 3'-UUG-5'. Keep in mind that adenine binds to uracil in RNA.

Codon:      5'-AAC-3'

Anticodon: 3'-UUG-5'

Anticodons are found on molecules of tRNA. Their function is to base pair with the codon on a strand of mRNA during translation. This action ensures that the correct amino acid will be added to the growing polypeptide chain. A tRNA molecule will enter the ribosome bound to an amino acid. The anticodon sequence will bind to the codon of the mRNA, allowing the tRNA to release the attached amino acid. This amino acid is then added to the peptide chain by the ribosome.

tRNA is a special type of RNA that has the function of forming bonds with amino acids and bringing them to ribosomes to complete translation. tRNA carries anticodons, allowing it to bind to mRNA in the active site of a ribosome. It can then transfer its amino acid residue to the ribosome, where it is incorporated into the growing polypeptide chain. The tRNA molecule is the released from the ribosome and recycled.

rRNA forms part of the ribosome structure and mRNA brings information from the nucleus to the cytoplasm. Transcription is the process of making an RNA transcript from a DNA template, and is performed by an RNA polymerase.

Amino acid sequence is determined by the sequence of codons on mRNA. tRNA is responsible for bringing new amino acids to the ribosome. Interactions between the codons on mRNA and the anticodons on tRNA are what allow the formation of the appropriate peptide bonds.

Chaperones are later used to facilitate the development of protein structure, but are not involved in checking protein sequence.

Aminoacyl-tRNA synthetase is responsible for "charging" tRNA with amino acids. During translation, tRNA molecules that are bound to specific amino acids are fed into the ribosome in a specific order that is complementary to the mRNA strand. Once a tRNA is used up, it loses its amino acid. As a result, it must interact with aminoacyl-tRNA synthetase before it can be used again in translation.

A malfunction in aminoacyl-tRNA synthetase would result in a shortage of charged tRNA molecules and a decrease in translation processing.

The three types of RNA discussed are messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). mRNA forms during transcription when RNA polymerase synthesizes RNA from the DNA template. Post-transcriptional modification is required for the mRNA to mature and exit the nucleus. Once in the cytoplasm, the mRNA will bind to a ribosome composed of rRNA and proteins. The ribosome will then recruit tRNA molecules to the complex in order to synthesize the protein product. Each amino acid binds to a specific kind of tRNA. tRNA brings the amino acids to the growing end of the newly forming polypeptide at the ribosome by binding to the codon of the mRNA.

The enzyme aminoacyl-tRNA synthetase joins tRNA molecules with a corresponding amino acid. First, an amino acid is bound to aminoacyl-tRNA synthetase using ATP. Then, the tRNA molecule containing the corresponding anticodon binds to the enzyme. The correct tRNA molecule is identified by aminoacyl-tRNA synthetase by its anticodon sequence and other areas of its structure. Last, the tRNA molecule covalently bonds to the amino acid and is released from aminoacyl-tRNA synthetase.

Ribosomes are non-membranous organelles that direct protein synthesis by reading mRNA and joining amino acids into strands of polypeptides. Ribosomes exist in both free and membrane-bound states. They are synthesized in both the nucleolus and cytoplasm. The components that make up these non-membranous organelles are rRNA molecules and a variety of proteins. Ribosomes have a large and a small subunit, together called the translational apparatus. The small ribosomal subunit reads the mRNA strand and the large ribosomal subunit joins amino acids into polypeptides. 

The large ribosomal subunit has three sites that interact with tRNA molecules—the peptidyl “P” site, the aminoacyl “A” site, and the exit “E” site. The P-site holds the tRNA corresponding to the most recently added amino acid, which is attached to the growing polypeptide chain by a peptide bond. The A-site holds the tRNA with the next amino acid to be added to the chain. Finally, the E-site holds the free tRNA without an amino acid that was previously in the P-site.

The mRNA strand is synthesized 5' to 3' and contains the codons. tRNA contains the anticodons needed for the corresponding amino acid, and is paired to the codon 3' to 5'.