Final answer:
Ribosomal RNA (rRNA) is integral to protein synthesis as it makes up the structure of ribosomes, aligns mRNA, and catalyzes peptide bond formation.
Step-by-step explanation:
The type of RNA that is a major component of the structure at which protein synthesis occurs is ribosomal RNA (rRNA). rRNA is not only a structural component of ribosomes, but it also has enzymatic functions. It is essential for the proper alignment of messenger RNA (mRNA) and ribosomes, and it catalyzes the formation of peptide bonds between amino acids during protein synthesis. This makes rRNA indispensable in the translation process where proteins are synthesized according to the code carried by mRNA.