Exam 14: From Dna to Protein: Gene Expression

If inosine were not present in anticodons, there would be _______ wobble, and _______ different types of tRNAs would be needed to match the different codons.

Stop codons on mRNA

If a strand of mRNA has the sequence 5ʹ-AUGUCA...GCUA-3ʹ (with [...] representing the intervening sequence), the template strand of DNA used to produce this mRNA was _______.

Arabidopsis thaliana, a plant in the mustard family, has a short generation time and can produce numerous progeny.It can be readily grown in the lab and is easy to manipulate genetically.It is thus considered a(n) _______ organism.

Suppose the coding region of a gene contains three exons with 360 nucleotides in exon 1, with 342 in exon 2, and with 450 in exon 3 (not counting the stop codon).A protein in a splice variant of the gene in which exon 2 was spliced out would be composed of _______ amino acids.

The genetic code is best described as

What is a major reason that the bread mold Neurospora is particularly useful in genetic studies?

The binding of snRNPs to consensus sequences is necessary for

Draw a figure showing ribosome structure and initiation, elongation, and termination of protein synthesis (at a minimum, include A, P, and E sites, codons and anticodons, tRNA, rRNA, and small and large subunits).Use sequence AUG CUU UAA, where AUG is the start codon, CUU codes for Leu, and UAA is the stop codon.

Exons are

The fidelity function is a function of the _______, and it ensures that _______.

In what way does RNA polymerase differ from DNA polymerase?

Cells have substantially _______ different tRNAs than codons because of the phenomenon called _______.

The tRNA moves between three sites along the ribosome: A, E, and P.In chronological order, what is the pattern of residence of a given tRNA molecule at those sites?

If the coding region of an mRNA is 2,400 nucleotides long, how many codons does it have?

Draw a figure of a eukaryotic cell, and show where in the cell the gene is transcribed and translated.In your figure, indicate how this particular gene product is targeted to a compartment in the cell such as the endoplasmic reticulum.Create a stepwise list of all the important proteins and enzymes required for this process.Imagine that the signal sequence has been deleted from this gene without deleting the start codon.How will this deletion affect gene expression? How will this deletion affect the targeting of the protein to the endoplasmic reticulum?

A mutation of a sigma factor in a bacterium would most likely affect

If the DNA encoding a nuclear signal sequence were placed in the gene for a cytoplasmic protein, the protein would

Suppose that a certain wild-type bacteria can synthesize substance D, but various mutant strains cannot.We know that substance D is synthesized from substance X in a pathway that involves three intermediate substances (A, B, and C), but we do not know the order of the steps in the pathway.The table shows four different mutant strains that have been tested for their ability to grow on the various substances.The "+" means that the strain can grow on that substance.The "‒" means that the strain cannot grow on that substance. What is the most likely order of the pathway? (For example, A  B  C  D indicates that substance A is converted to substance B, which is converted to substance C, which is converted to substance D.)

The phenotype of an organism is primarily determined by the activity of _______.