Transcription

Which of the following represents the flow of genetic information in organisms?

• RNA → DNA → Protein
• DNA → RNA → Protein
• Protein → RNA → DNA
• DNA → Protein

Which of the following best describes an mRNA molecule?

• It is made out of A, T, C, and G bases from an RNA template

• It is made from a DNA template, is single stranded, and has a 5' cap and 3' Poly-A tail.

• It is usually double stranded and made by connecting RNA nucleotides in random order

• It is made using the sequence of amino acids in a completed protein.

Which enzyme is responsible for making an mRNA transcript?

• DNA polymerase

• RNA polymerase

• ATP synthase

• RNA Helicase

The first 10 nucleotides from the GFP protein are listed below. What would be the corresponding mRNA molecule made from this gene sequence? TACGCATTTC

• AUGCGUAAAG
• ATGCGTAAAG
• UACGCAUUUC
• TACGCATTTC

The DNA template for a gene is typically read from 3' to 5'. Given this, in which direction will the mRNA transcript be made?

• from 3' to 5'

• from 5' to 3'

• either direction, 3' to 5 or 5' to 3'

• It will depend on which strand of the DNA is the template

Answer explanation

RNA polymerase can only add on to the 3' end of a DNA strand so the mRNA can only be made in the 5' to 3' direction

The genetic code is said to be degenerate. This means that…

• Most amino acids have more than one corresponding codon.
• Each nucleotide codes for a different amino acid.
• An amino acid can pair with any codon.
• Every amino acid is matched with only one codon.

One codon in a gene sequence mutates from GGC to GGG. Another codon mutates from AAT to GAT. Which of these mutations is more likely to impact the amino acid chain made from this gene?

• GGC to GGG
• Neither is likely to impact the amino acid chain.
• AAT to GAT
• They are equally as likely to impact the amino acid chain.

What would be the most likely effect of a gene losing its promoter region?

• The level of transcription would decrease but still continue.
• There would be no change in the level of transcription.
• The RNA polymerase would not know where to bind and the gene would not be transcribed.
• The level of transcription would increase since there is no longer a place for negative control proteins to bind.

Which of the following is true about RNA polymerase? (choose all that apply)

• It matches free RNA nucleotides to both strands of DNA at the same time.
• It only matches RNA nucleotides to one strand of DNA, the template strand.
• It elongates the RNA molecule from 5’ to 3’
• It can only add nucleotides to the 5’ end of the RNA molecule.
• It attaches to and transcribes sections of DNA randomly into sections of RNA.

In a eukaryotic gene, the parts of the gene that do not code for amino acids are called...

• exons.

• introns.

• the start codons.

• the spliceosomes.