Exam 6: Anatomy and Function of a Gene: Dissection Through Mutation

A mutation that changes a codon sequence,and subsequently changes the amino acid that should have been placed at that point in the polypeptide chain,is called a

Assume that for a given gene a mutation creates an allele that functions as a dominant negative.The gene codes for a protein that forms a trimer within the cell.If at least one of the subunits has the mutant structure the entire protein is inactivated.For a heterozygous individual,what percent of the trimers present in the cell will be inactive?

What would happen in a cell that completely lacked aminoacyl-tRNA synthetases?

In the usual flow of genetic information (often called the Central Dogma),which of the following best represents the expression of genes?

In your studies of an unusual prokaryotic organism,you have cloned and sequenced an interesting gene and the protein that it codes.Although you have sequenced the gene several times,the start codon is always read as GTG instead of ATG.How do you interpret this result?

Describe nonsense suppression.

What would happen if all of the snRNAs were removed from a cell?

As compared to subunit vaccines,what is the main advantage of the "killed whole virus" HIV vaccine under development in Canada?

rRNA carries an anticodon,which is the complementary sequence to the mRNA codon that specifies a particular amino acid.

Mutations that abolish the function encoded by the wild-type allele are known as

Mutations that result in much less of a protein or a protein with limited function are known as

Distinguish between neomorphic,hypomorphic,and hypermorphic mutations.

RNA molecules that can act as enzymes and catalyze specific biochemical reactions are known as ________________.

Aminoacyl-tRNA synthetase is the enzyme that

A(n)_____________ consists of proteins and small nuclear RNAs forming discrete particles that mediate splicing.

Frameshift mutations occur when the number of bases inserted or deleted is not a multiple of three.

Protein synthesis begins with the amino acid ___________ as its codon is the one used as the "start codon" by nearly all organisms.

The restoration of gene function by one mutation canceling another in the same gene is known as intragenic suppression.

Capping enzyme and methyl transferases are needed to add a 5' cap on mRNA.

Except in reverse transcription,RNA is synthesized in a 3' to 5' fashion.