RNA polymerases tend to transcribe much more slowly than DNA

RNA polymerases tend to transcribe much more slowly than DNA polymerases do during DNA replication. Why does this make sense?

Solution

The DNA polymerase copies DNA strand in small fragments and later all the fragmentsd are joined by DNA ligase enzyme. Sythesizing small fragments of DNA makes the process faster. In contrast, RNA polymerase synthesizes mRNA using DNA strand as template. The RNA is synthesized at a stretch and unwind the DNA from time to time. This makes to invest more time for synthesis of RNA. DNA is unwound and the two strands are separated at a time during the process replication. Moreover, the fragments are synthesized and later joined. Thus, DNA polymerase synthesizes DNA faster than RNA polymerase transcribing DNA into RNA.