Question

Which of the following statements about eukaryotic RNA polymerases is true?

a) They only transcribe mRNA.
b) They lack proofreading capabilities.
c) They require a primer for transcription.
d) They transcribe all types of RNA.

Answer 1

Eukaryotic cells use three different RNA polymerases to transcribe all types of RNA, including mRNA, rRNA, and tRNA, among others.

Step-by-step explanation:

In eukaryotic cells, there are three distinct types of RNA polymerases that transcribe different classes of RNA. The correct statement about eukaryotic RNA polymerases is that they transcribe all types of RNA. Specifically, RNA polymerase I synthesizes rRNA, RNA polymerase II is responsible for all protein-coding genes that make mRNA, and RNA polymerase III handles tRNA, 5S rRNA, and other small nuclear RNAs. These polymerases differ from their prokaryotic counterparts, which use a single polymerase for all RNA synthesis, and unlike prokaryotic polymerases, eukaryotic RNA polymerases do not require a primer to initiate transcription, nor do they possess proofreading capabilities.