Mutations Milestones Review

5′ G T A             A A 3′

3′ C A T G C A T T 5′

This segment of DNA has undergone a mutation in which three nucleotides have been deleted.  A repair enzyme would replace them with

Hemoglobin is a protein found in red blood cells of vertebrates and in the plasma of many invertebrates.  The function of this protein is to transport oxygen throughout the body and to bring carbon dioxide back to be expelled from the organism.  If the amino acid sequence of the protein is altered, the mutated protein is not as efficient at carrying oxygen as is the normal hemoglobin.  Which argument is supported by this information?

Different types of mutations can occur in DNA.  The diagram represents a type of mutation.

Which statement describes the mutation in the diagram?

A substitution mutation occurs in a DNA sequence, as represented below.

Normal:      TAC  GCC  AAG  ATT

Mutated:    TAC  GCC  AGG  ATT

The table below shows the mRNA codons for some amino acids.

Based on this information, what is the expected effect of the mutation?

Which of the following describes a mutation in a parent that could change the phenotype of its future offspring?

The sequence of bases in a nucleotide of DNA makes up an organism’s genetic code.  How could a change in a sequence of DNA bases affect an organism?

Sickle-shaped red blood cells result from a mutation in the gene that codes for hemoglobin.  This mutation results in sickle-cell anemia.  A partial sequence of bases from a normal hemoglobin gene and a sequence that results in sickle-cell anemia are shown below.

Normal hemoglobin:                 T-G-A-G-G-T-C-T-C-C-T-C

Sickle-cell hemoglobin:           T-G-A-G-G-T-C-A-C-C-T-C

What types of mutation is depicted in this sequence?

A mutation is least likely to affect a cell when the mutation

An inversion occurs along part of a chromosome.  How does the inversion most likely affect the region in which it occurs?

A mutation in the DNA that produced the strand of messenger RNA shown in the chart below produced a new strand of mutant messenger RNA.

ACUACGUCGAAA

If the mutation was a deletion, which strand of the following sequences would best represent the resulting mutant messenger RNA?

Which condition would most likely result in an increase in the phenotypic variation within a population?

The base sequences below show two different sequences of the same gene.

Wild Type:  TTGACTCGGTATAC

Mutant:       TTGACTCGTATAC

What type of mutation is illustrated?

Write the messenger RNA sequences that would be produced from the normal DNA sequence shown above.

According to the genetic code, the mRNA codons UGU and UGC code for the amino acid cysteine, the mRNA codon UGA is a stop codon, and the mRNA codon UGG codes for the amino acid tryptophan.  What would a mutation in the second base of the codon UGA likely mean for the resulting protein?

Hemoglobin is a protein found in red blood cells of vertebrates and in the plasma of many invertebrates.  The function of this protein is to transport oxygen throughout the body and to bring carbon dioxide back to be expelled from the organism.  If the amino acid sequence of the protein is altered, the mutated protein is not as efficient at carrying oxygen as is the normal hemoglobin.  Which argument is supported by this information?

Why can the deletion of a single nitrogen base in DNA due to a mutation be harmful to an organism?

Which one of the following scenarios is not an example of a heritable mutation caused by environmental factors.

A codon chart is shown below.

Which of these changes to the DNA triplet 3′ GCT 5′ will affect the protein produced?

Mutations have various effects on the amino acid sequence that determines protein structure and function.  A silent mutation has no effect on the protein’s function.  Which mutation would result in a silent mutation?

The base sequences below show two different sequences of the same gene.

Wild Type:  TTGACTCGGTAT

Mutant:       TTGACTCGTATA

What type of mutation is illustrated?

Match the types of genetic mutations of the following DNA sequence below.

AAGACTCGG

What occurs during frameshift mutation?