Mutations Quiz

Which of the following statements about somatic mutations is FALSE? - They may result from both frameshift and base-pair substitution mutations - They may be inherited in the offspring of mutated individuals - They may be inherited by daughter cells after cell division - Some may give rise to cancers in humans and other animals - They may result in inactive gene products of the mutated genes

They may be inherited in the offspring of mutated individuals

Which of the following DNA repair systems does not involve the activity of a DNA polymerase? - nucleotide-excision repair in yeast - all of the above in the activity of a DNA polymerase - photoreactivation in E. coli - base-excision repair in E. coli - mismatch repair in humans

photoreactivation in E. coli

Frameshift mutations: - usually produce nonfunctional proteins - occur when DNA polymerase makes a mistake when copying long stretches of the same nucleotide - are caused by UV light - change many codons

- usually produce nonfunctional proteins - occur when DNA polymerase makes a mistake when copying long stretches of the same nucleotide - change many codons

Assume that you have discovered a new chemical mutagen that modifies guanine so that is mispairs with adenine when adenine is in the template DNA strand during DNA replication. However, this mispairing is limited to when the modified guanine is being added to the newly replicating DNA strand. When the modified guanine is in the template DNA strand it always pairs normally with cytosine being added to the growing newly synthesized strand. What type of mutation would you predict would be caused by the new chemical mutagen? - A-to-C base substitutions - G-to-T base substitutions - A-to-G and A-to-C base substitutions - A-to-T base substitutions - A-to-G base substitutions

A-to-C base substitutions

The type of mutation that reverses the effects of a frameshift mutation without changing the frameshift and occurs with the same gene as the frameshift is called a(n): - silent mutation - nonsense mutation - missense mutation - intragenic suppressor mutation - intergenic suppressor mutation

intragenic suppressor mutation

Which of the following types of mutations does NOT lead to a change in the amino acid sequence of the gene product? - Silent - Neutral - Missense - Loss-of-function - Nonsense

silent

DNA polymerase's ability to proofread during replication should prevent: - damage caused by deamination - damage caused by alkylating agents - the incorporation of the wrong nucleotide because of wobble pairing - the effects of transposable elements - thymine dimers

the incorporation of the wrong nucleotide because of wobble pairing

Heterozygotes exhibit the dominant phenotype because: - the dominant allele overpowers the recessive allele - all copies of the gene are producing functional proteins - they still have one one copy of the gene producing a functional protein - none of the copies of the gene are producing functional proteins

they still have one one copy of the gene producing a functional protein

Spontaneous causes of mutation would include: - mistakes that occur during replication due to wobble pairing between nitrogenous bases - exposure to nitrous acid - exposure to uv light - reactions of nitrogenous bases with water that alter the base pairing rules for the molecule - strand slippage that occurs when a repeated sequence of nucleotides gets replicated - exposure to x rays or other forms of radiation - segments of DNA that randomly insert themselves at various places along the chromosome

- mistakes that occur during replication due to wobble pairing between nitrogenous bases - reactions of nitrogenous bases with water that alter the base pairing rules for the molecule - strand slippage that occurs when a repeated sequence of nucleotides gets replicated - segments of DNA that randomly insert themselves at various places along the chromosome

Which of the following is true of deamination: - occurs spontaneously in an aqueous environment - it creates frameshift mutations - it involves the removal of NH2 from a nitrogenous base - it creates an AP site - it is responsible for the conversion of cytosine to uracil

- occurs spontaneously in an aqueous environment - it involves the removal of NH2 from a nitrogenous base - it is responsible for the conversion of cytosine to uracil