Answer:
ribosomes.
Step-by-step explanation:
The process of protein synthesis involves two main stages: transcription and translation. In transcription, the DNA sequence in the nucleus is used to create a complementary messenger RNA (mRNA) molecule. This mRNA molecule then leaves the nucleus and travels to the cytoplasm, where it binds to a ribosome.
The ribosome is the site of translation, where the mRNA sequence is used to direct the assembly of a polypeptide chain. The ribosome reads the mRNA sequence in groups of three nucleotides, called codons, and matches each codon with the appropriate amino acid. The ribosome then links the amino acids together in the correct order to form a polypeptide chain.
The ribosome is made up of two subunits, a large subunit and a small subunit, which come together around the mRNA molecule. The ribosome also contains three binding sites for tRNA molecules, which are small RNA molecules that carry specific amino acids. The tRNA molecules bind to the ribosome and deliver their amino acids to the growing polypeptide chain, based on the sequence of codons in the mRNA molecule.
Overall, the ribosome plays a crucial role in protein synthesis by providing the site for the assembly of polypeptide chains. The mRNA molecule carries the genetic information from the nucleus to the ribosome, where it is used to direct the synthesis of proteins. The ribosome reads the mRNA sequence and matches each codon with the appropriate amino acid, using tRNA molecules to deliver the amino acids to the growing polypeptide chain.