Answer:
The nucleolus refers to a condensed region of chromatin where the production of ribosomes takes place. Ribosomes are the regions of protein synthesis, which perform this function by aligning the amino acids in a suitable sequence, as directed by the messenger RNA.
The ribosomes are generally found entrenched in the endoplasmic reticulum. The production of a huge amount of proteins is possible due to the presence of very large surface area provided by the ER to the ribosomes. The prime function of the ER is to transport the newly formed proteins over to the Golgi apparatus.
The main function of the Golgi apparatus is to amend the proteins and administer them into the vesicles. From here they are mediated towards different cell parts. Hence, the mentioned cell organelles are associated with their activities of synthesis of proteins and transportation.