The nucleus contains DNA in the form of chromosomes. The DNA gets transcribed into mRNA which is translated by the ribosomes into . When a certain function is needed in the cell cellular signals (proteins hormones etc) will activate transcription leading to the production of proteins that will perform the necessary function.
The ER is like the cell’s highway; the Golgi apparati package and tag protein products so that they safely get where they need to go.
So:
nucleus: has DNA which are like the instructions
ribosomes: the elves that do the work
ER: the conveyer belt
Golgi: the FedEx departmenthttps://answers.yahoo.com/question/index?qid=20070829171531AAEBiWd