Prompt Set #9

How might a single base substitution in the sequence of a gene affect the amino acid sequence of a protein encoded by the gene, and why? A. Only a single amino acid could change, because the reading frame is unaffected B. The amino acid sequence would be substantially altered, because the reading frame would change with a single base substitution C. All amino acids following the substitution would be affected, because the reading frame would be shifted D. It is not possible for a single base substitution to affect protein structure, because each codon is three bases long

A. Only a single amino acid could change, because the reading frame is unaffected

An original section of DNA has the base sequence 3'- TAC GTT ACC GTC -5' The protein synthesized from this template DNA strand would be: A. Tyr Val Thr Val B. Met Gln Trp Gln C. Leu Pro Leu His D. Asp Gly Asn Val

B. Met Gln Trp Gln

Which of the following types of mutations, resulting in an error in the mRNA just after the AUG start of translation, is likely to have the most serious effect on the protein product? A. deletion of a codon B. deletion of 2 nucleotides C. substitution of the 3rd nucleotide in an ACC codon D. a substitution of the first nucleotide of a GGG codon

B. deletion of 2 nucleotides

An original section of DNA has the base sequence 3' - TAC GTT ACC GTC -5' A mutation in this DNA strand results in the base sequence 3' - TAG CGT TAC CGT C -5'. This change represents _____. A. a missense mutation B. a silent mutation C. a frameshift mutation D. an in frame insertion

C. a frameshift mutation

A nonsense mutation can result from A. a deletion of a nucleotide that results in a frameshift and formation of an early stop codon B. an insertion of a UGA codon C. a point mutation of a CGA codon to a UGA codon D. a point mutation from a AAG codon to a AUG codon

C. a point mutation of a CGA codon to a UGA codon

A nonsense mutation in a gene:___ A. changes an amino acid in the encoded protein to a different amino acid B. has no effect on the amino acid sequence of the encoded protein C. introduces a premature stop codon into the mRNA D. alters the reading frame of the mRNA

C. introduces a premature stop codon into the mRNA

Because the genetic code is non-overlapping, a missense mutation results in the alteration of ______________, and the resulting protein has ______________. A. only one codon / at least three amino acid changes B. three codons / a single amino acid change C. only one codon / a single amino acid change D. three codons / three amino acid changes

C. only one codon / a single amino acid change

An original section of DNA has the base sequence 3'- TAC GTT ACC GTC -5' The mRNA synthesized from this template DNA strand would be: A. 3'- TAC GUU ACC GUC -5' B. 5'- TAC GUU ACC GUC -3' C. 3'- AUG CAA UGG CAG -5'. D. 5'- AUG CAA UGG CAG -3'.

D. 5'- AUG CAA UGG CAG -3'.

You have the sequence . 5'- CGA AUG CCC GAA CAC GUC UGA GGG - 3' If a U was inserted between the second and third codon, what will the effect be on the resulting protein? A. there will be no change in the amino acid sequence of the protein B. one amino acid will be changed to another amino acid C. the protein will be longer D. The protein will be shorter

D. The protein will be shorter

An original section of DNA has the base sequence 3' - TAC GTT ACC GTC -5' A mutation in this DNA strand results in the base sequence 3' - TAC CAC GTT ACC GTC -5'. This change represents _____. A.a missense mutation B. a silent mutation C. a frameshift mutation D. an in-frame insertion

D. an in-frame insertion