Exam 12: The Genetic Code and Transcription

A class of mutations that results in multiple contiguous (side-by-side)amino acid changes in proteins is probably caused by which one of the following types of mutations?

A 5'-cap describes the addition of a base,usually thymine,to the 5' end of a completed peptide.

Transcription factors function to help move ribosomes along the mRNA.

What is the name given to the three bases in a messenger RNA that bind to the anticodon of tRNA to specify an amino acid placement in a protein?

The genetic code is fairly consistent among all organisms.The term often used to describe such consistency in the code is ________.

RNA processing occurs when amino acids are removed from nascent proteins.

The triplet AUG is commonly used as a start codon during translation.

The finding that virtually all organisms use the same genetic code provides the basis for declaring that the code is universal.Name at least two exceptions to such universality.

Regarding the efficient initiation of transcription by RNA polymerase II,which specific "upstream" signals appear to be involved?

In which cellular organelle do the three posttranscriptional modifications often seen in the maturation of mRNA in eukaryotes occur?

Messenger RNA is usually polycistronic in eukaryotes.

In 1964,Nirenberg and Leder used the triplet binding assay to determine specific codon assignments.A complex of which of the following components was trapped in the nitrocellulose filter?

In the context of molecular genetics,how does one reconcile the terms overlapping genes and nonoverlapping code?

Significant in the deciphering of the genetic code was the discovery of the enzyme polynucleotide phosphorylase.What is this enzyme used for?

An intron is a section of an RNA that gets spliced out.

"Breaking the genetic code" has been referred to as one of the most significant scientific achievements in modern times.Describe (in outline or brief statement form)the procedures used to break the code.

The enzyme polynucleotide phosphorylase is capable of generating a random assembly of ribonucleotides.

Referring to the genetic code,what is meant by "wobble"?

The code is nonoverlapping,meaning that,assuming "standard translation," a given base participates in the specification of one and only one amino acid.

If one compares the base sequences of related genes from different species,one is likely to find that corresponding ________ are usually conserved,but the sequences of ________ are much less well conserved.