Molecular Biology: Transcription and mRNA Synthesis

What determines where transcription begins and ends in a DNA molecule?

Specific sequences of nucleotides along DNA

Which type of RNA polymerase is responsible for synthesizing all RNA molecules in bacteria?

One type of RNA polymerase

What is the role of the promoter sequence in transcription?

To determine which strand of the DNA helix is the template

What is the function of RNA polymerase in transcription?

To separate the DNA strands and join RNA nucleotides Signup and view all the answers

What is the sequence of amino acids coded by the mRNA molecule transcribed from the DNA portion 5'-TAC TAA GTA ACA TCG CCC 5'?

Met - Ile - His - Cys - Ser - Gly Signup and view all the answers

What is a transcription unit?

A region of DNA that is transcribed into a single mRNA molecule Signup and view all the answers

In prokaryotes, what is the relationship between transcription and translation?

Transcription and translation occur simultaneously. Signup and view all the answers

What is the primary function of a codon in mRNA?

To specify one of the 20 amino acids. Signup and view all the answers

What is the relationship between the number of nucleotides in mRNA and the number of amino acids in a protein?

The number of nucleotides is three times the number of amino acids. Signup and view all the answers

What is the purpose of RNA processing in eukaryotes?

To convert pre-mRNA to mRNA. Signup and view all the answers

What is the function of stop codons in mRNA?

To signal the end of translation. Signup and view all the answers

How many codons specify amino acids?

61 codons. Signup and view all the answers

What is the function of the TATA box in eukaryotic genes?

To mediate the binding of RNA polymerase II to the promoter Signup and view all the answers

What is the stretch of DNA that is transcribed into an mRNA molecule called?

Transcription unit Signup and view all the answers

In eukaryotes, what recognizes and binds directly to the promoter region?

Transcription factors Signup and view all the answers

During elongation, how many bases are untwisted by RNA polymerase at a time?

10 to 20 bases Signup and view all the answers

What is the direction of RNA synthesis during transcription?

′ to ′ Signup and view all the answers

What signals the termination of transcription?

The transcription of a specific sequence in the DNA Signup and view all the answers