Target Exam

CUET

Subject

Biology

Chapter

Molecular Basis of Inheritance

Question:

Which enzyme in bacteria is responsible for catalyzing the transcription of all types of RNA (mRNA, tRNA, and rRNA)?

Options:

DNA-dependent RNA polymerase

DNA-dependent DNA polymerase

RNA-dependent RNA polymerase

RNA-dependent DNA polymerase

Correct Answer:

DNA-dependent RNA polymerase

Explanation:

The correct answer is Option (1) - DNA-dependent RNA polymerase

In bacteria, there are three major types of RNAs: mRNA (messenger RNA), tRNA (transfer RNA), and rRNA (ribosomal RNA). All three RNAs are needed to synthesise a protein in a cell. The mRNA provides the template, tRNA brings aminoacids and reads the genetic code, and rRNAs play structural and catalytic role during translation. There is single DNA-dependent RNA polymerase that catalyses transcription of all types of RNA in bacteria. RNA polymerase binds to promoter and initiates transcription (Initiation).