The DNA contains the code for thousands and thousands of different proteins. Each one of the DNA segments constitutes a gene. Other regions of DNA hold the data for making several other addition types of RNA, each one which carries out a specific role. Transcription is the process of copying a gene into an mRNA, tRNA, or any other RNA molecule. The other major function of the cell nucleus is referred to as replication.
Replication is the duplication of the DNA into the chromatin.
Just before cell division, all the DNA and chromatin are doubled, to make two replicated cells. The cytoplasm of eukaryotic cells is packed with ribosomes, vesicles, and organelles, which are separated by boundary membranes, and all have a specialized function or activity within the eukaryotic cell. The ribosomes have several functions, among them protein synthesis, which is also referred to as translation. In this function, a ribosome starts at the beginning of the coding portion of a mRNA molecule, and reads the translation code as it moves through the molecule. While moving, the ribosomes begin to assemble the amino acids into a protein chain.