Exam 14: From Dna to Protein: Gene Expression

Refer to the figure, which shows the genetic code. Which single base substitution in the coding strand of DNA would result in premature termination of translation?

A strain of Neurospora is able to grow on minimal medium.When substance A is added to the medium, however, the strain cannot grow.Supplying a small amount of substance B has no effect on the strain, but it cannot reverse the effect of substance A.Supplying a small amount of substance C, by contrast, enables the strain to grow with substance A.Which of the following statements best explains these facts?

Refer to the figure. Which process or technique is being shown?

The modified GTP cap on eukaryotic mRNAs is found

Translate the following mRNA: 3-GAUGGUUUUAAAGUA-5

A researcher compares the dog and human sequences of gene X and its protein product.The nucleotide sequences of the two different species' genes are 87 percent identical, whereas the amino acid sequences of the proteins are 99 percent identical.The discrepancy between the nucleotide and amino acid levels of sequence identity is possible because the genetic code is _______.

Suppose that the genetic code involved five nucleotides per codon but that there were only two different types of nucleotides.How many different codons would be possible?

The three codons in the genetic code that do not specify amino acids are called

The table shows the biochemical pathway of arginine production and growth of Neurospora under various conditions. Wild-type Neurospora was treated with X-rays to induce heritable mutations.Treated Neurospora was grown on minimal medium ("no addition" in the table) and minimal medium supplemented with the compounds indicated in the table.Growth is indicated as dry weight of fungal material after 5 days.Here we see the results of three mutated strains that were linked to the metabolic pathway that generates arginine.Without arginine production, Neurospora cannot grow. Considering the biochemical pathway of arginine production, what explanation could account for the ability of strains 34105 and 33442 but the inability of strain 36703 to show some growth on minimal medium?

By convention, DNA sequences are written starting with the _______ end of the _______ strand.

Suppose that the coding region of a gene contains 1,800 base pairs, with 570 in exon 1, with 420 in exon 2, and with 810 in exon 3 (not counting the stop codon).The protein translated from this gene will consist of _______ amino acids.

Which feature makes tRNA unique compared with other functional RNAs?