1. Transcription: This stage occurs in the nucleus of a eukaryotic cell (or the cytoplasm of a prokaryotic cell). During transcription, the genetic information stored in DNA is copied into a messenger RNA (mRNA) molecule.

* The DNA sequence is read by an enzyme called RNA polymerase, which builds a complementary mRNA molecule.

* The mRNA then leaves the nucleus (in eukaryotic cells) and travels to the ribosomes.

2. Translation: This stage occurs in the cytoplasm of the cell, specifically at the ribosomes. During translation, the mRNA sequence is read by the ribosome and used to build a chain of amino acids, which will eventually fold into a functional protein.

* The mRNA sequence is read in groups of three nucleotides called codons, each of which codes for a specific amino acid.

* Transfer RNA (tRNA) molecules bring the appropriate amino acids to the ribosome, where they are linked together to form a polypeptide chain.

Therefore, the two main stages of protein synthesis are transcription in the nucleus and translation in the cytoplasm.