Exam 18: Gene Expression: Ithe Genetic Code and Transcription

RNA proofreading is ________ stringent than DNA proofreading.

In eukaryotic cells,we sometimes find reverse transcriptase activity,even though the cells are not infected with a retrovirus.This activity can be attributed to

Answer the questions below based on this RNA sequences: 5'-AUGAUGAUGAUG-3' This RNA transcript was generated using a synthetic DNA template. The letters B, D, E, F, G, and H have been selected to represent different amino acids. Assume that each codon is a different amino acid -Imagine that the genetic code were read in a non-overlapping fashion,using only two nucleotides to specify an amino acid (i.e.,the sequence above would be read: AU-GA-UG and so on).Which of the following polypeptides would be obtained by translating the sequence above?

Consider the following double-stranded DNA sequence that codes for a short polypeptide. 5'-A-T-G-T-G-G-C-C-A-C-T-A-T-A-A-T-C-A-3' 3'-T-A-C-A-C-C-G-G-T-G-A-T-A-T-T-A-C-T-5' Which strand is the coding strand,and where is the N-terminal end of the resulting peptide located?

Which of the following enzymes is associated with "transcription factories" in the nucleus?

In the absence of retroviruses,reverse transcription may occur in eukaryotes if which of the following is present?

Which of the following is associated with the production of multiple mRNAs from a single gene?

Which of the following enzymes is required in order to produce DNA molecules complementary to mRNA transcripts?

Answer the questions below based on this RNA sequences: 5'-AUGAUGAUGAUG-3' This RNA transcript was generated using a synthetic DNA template. The letters B, D, E, F, G, and H have been selected to represent different amino acids. Assume that each codon is a different amino acid -Imagine that the genetic code were read in a non-overlapping fashion,using four nucleotides to specify each amino acid (i.e.,the sequence above would be read: AUGA-UGAU-GUAG).Which of the following polypeptides would be obtained by translating the sequence above?

The 21st and 22nd amino acids found in proteins are the rare amino acids ________ and ________.

The technique initially used in the identification of promoter sequences was ________.

A mutation that results in the addition or deletion of a single nucleotide and therefore radically changes the amino acid sequence of the resulting polypeptide is known as a ________ mutation.

One of the NASA rovers returns from its mission with a variety of samples.From one sample the rover has isolated and cultured a unique prokaryotic species that contains many novel amino acids,causing scientists to hypothesize that the genetic code may be different in this organism.Your job is to investigate whether or not the genetic code uses overlapping or non-overlapping codons.Another researcher has data suggesting that rather than codons of three nucleotides,this organism uses groups of four nucleotides.Show how you would verify the presence of overlapping versus non-overlapping codon frames and how you could tell if the codons use three or four nucleotides.Use the following test mRNA sequence in your experiment. Test mRNA sequence: 5'-AUUGGCCAAUUUACGGUAAUGGCCAAUUUACGGU-3'

________ are nonviral genetic elements that have reverse transcriptase activity.

Which of the following amino acids is not one of the 20 common amino acids found in cells?

________-driven promoters do not contain TATA boxes or BREs.

In some organisms,a normal stop codon,UGA,encodes for the amino acid

RNA has many functions in a cell.Besides mRNA,which carries information from the genome to the translation machinery,and rRNA,which is part of ribosomes and catalyzes the formation of peptide bonds,name three other types of RNA and describe the function of each.

In some organisms,a special tRNA recognizes the UAG stop codon but incorporates the amino acid

During eukaryotic transcription,TFIID recognizes and binds the ________ box in the DNA.