University of Central Florida (UCF) BSC2010C Biology I Practice Exam 4

Ribosomal RNA (rRNA) is considered the most abundant type of RNA in the cell. It is a critical component of ribosomes, the cellular machinery responsible for protein synthesis. Ribosomes consist of two subunits, each comprised of rRNA and proteins. The presence of rRNA in both the large and small subunits of the ribosome plays a vital role in translating messenger RNA (mRNA) into proteins.

In a typical cell, the amount of rRNA far exceeds that of other types of RNA because ribosomes are abundant and continuously active in the process of translation. This high concentration allows for efficient protein synthesis, which is essential for cell function and growth. While mRNA, transfer RNA (tRNA), and small nuclear RNA (snRNA) all have important roles in gene expression and processing, their overall abundance in relation to rRNA in the cell is significantly lower.