Final answer:
Ribosomal RNA (rRNA) is a component of ribosomes, which are found in the cytoplasm and associated with rough ER in cells and are critical for translation, the process of protein synthesis. The rRNA provides both structural and catalytic roles in the ribosome, and it is synthesized in the nucleolus.
Step-by-step explanation:
Ribosomal RNA (rRNA) is found in the ribosomes of a cell and is essential for protein synthesis. Many of a cell’s ribosomes are found associated with the rough endoplasmic reticulum (ER) and are involved in synthesizing proteins that are destined for the Golgi apparatus.
Ribosomes are composed of two subunits, a large and a small one, which are assembled in the nucleolus. These rRNA molecules provide a platform for translation, aligning the mRNA molecule with transfer RNA (tRNA) to synthesize proteins.
Moreover, rRNA is not involved in transcription, which is the first step of protein synthesis where mRNA is produced; instead, it plays a critical role in translation, the process by which the mRNA code is translated into a protein. rRNA contributes to the structural and catalytic components of the ribosome.
In eukaryotic cells, the rRNAs are synthesized by RNA polymerase I and include 5S, 18S, 28S, and 5.8S, while in prokaryotes they include 5S, 23S, and 16S rRNAs.