Transcription Quiz

What is the main transcription enzyme?

• Helicase

• Ligase

• RNA polymerase

• DNA polymerase

Answer explanation

The main transcription enzyme is RNA polymerase, which is responsible for synthesizing RNA from a DNA template during transcription.

What is the first step of gene expression?

• Mutation

• Transcription

• Replication

• Translation

Answer explanation

The first step of gene expression is Transcription, where the DNA sequence is copied into mRNA by RNA polymerase.

Which DNA strand is used as a template during transcription?

• Template strand

• Non-template strand

• Coding strand

• mRNA strand

Answer explanation

During transcription, the DNA template strand is used to synthesize an mRNA molecule, making it the correct choice for this question.

What is the role of the TATA box in eukaryotic promoters?

• Initiation site

• Transcription termination

• Promoter recognition

• Elongation signal

Answer explanation

The TATA box in eukaryotic promoters plays a role in promoter recognition, facilitating the binding of transcription factors and RNA polymerase to initiate transcription.

In which direction does RNA polymerase build a new RNA strand?

• Random

• Bidirectional

• 3' to 5'

• 5' to 3'

Answer explanation

RNA polymerase builds a new RNA strand in the 5' to 3' direction, following the template strand in the 3' to 5' direction.

What happens during the elongation stage of transcription?

• RNA strand gets shorter

• RNA polymerase binds to DNA

• RNA strand gets longer

• RNA is processed into protein

Answer explanation

During the elongation stage of transcription, the RNA strand gets longer as RNA polymerase moves along the DNA template and adds complementary nucleotides.

What is the process of ending transcription called?

• Elongation

• Initiation

• Termination

• Translation

Answer explanation

The process of ending transcription is called Termination, where the RNA polymerase stops transcribing the DNA sequence.

Which termination strategy is found in bacteria and involves a protein called Rho factor?

• Transcript termination

• Rho-dependent termination

• Rho-independent termination

• Polymerase termination

Answer explanation

Rho-dependent termination is the termination strategy found in bacteria that involves a protein called Rho factor.

What happens in Rho-independent termination in bacteria?

• RNA polymerase catches up with DNA

• RNA polymerase stalls

• RNA transcript folds back on itself

• RNA polymerase binds to Rho factor

Answer explanation

In Rho-independent termination in bacteria, the RNA transcript folds back on itself to form a hairpin loop, causing RNA polymerase to stall and detach from the DNA.

What is the RNA transcript called after termination in eukaryotes?

• snRNA

• mRNA

• rRNA

• tRNA

Answer explanation

The RNA transcript called after termination in eukaryotes is mRNA, which carries the genetic information from DNA to the ribosome for protein synthesis.