The tiny round factory you are describing is called a ribosome.

Here's why:

* Protein Synthesis: Ribosomes are the sites of protein synthesis. They read the genetic code carried by messenger RNA (mRNA) and use it to assemble amino acids into polypeptide chains, which fold into functional proteins.

* Endoplasmic Reticulum: Ribosomes are often found attached to the endoplasmic reticulum (ER), particularly the rough ER. This association allows proteins synthesized by the ribosomes to be directly inserted into the ER lumen or membrane, where they can be further modified, folded, and transported to their final destinations.

Let me know if you have any other questions!