MCB 181 Review Quiz 11

The enzyme _____ repairs 99% of mismatched bases immediately during replication. a. DNA polymerase b. AP endonuclease c. None of the answer options is correct. d. DNA ligase e. uracyl glycosylase

a. DNA polymerase

Chromosomes in which the normal order of a block of genes is reversed contain a(n): a. inversion. b. reciprocal translocation. c. insertion. d. duplication. e. None of the answer options is correct.

a. inversion.

In recombinant DNA experiments, _____ is used to cut pieces of DNA, and _____ joins these segments to form recombinant DNA. a. a restriction enzyme; DNA ligase b. DNA ligase; a restriction enzyme c. a RNA polymerase; a restriction enzyme d. a DNA polymerase; DNA ligase e. DNA ligase; a plasmid

a. restriction enzyme; DNA ligase

In DNA editing by means of CRISPR, the function of the CRISPR-associated protein is to: (Select all that apply.) a. transcribe CRISPR RNA. b. cleave target DNA. c. translate CRISPR RNA. d. bind target DNA. e. bind CRISPR RNA.

b and d?

DNA repair: a. always prevents errors. b. can involve excision of bases flanking a distortion in the helix. c. involves a set of proteins that are always active. d. can fix chromosomal inversions and translocations. e. is only active during DNA replication.

b. can involve excision of bases flanking a distortion in the helix.

Chromosomal mutations that are MOST likely to cause serious damage to an organism are those that affect the: a. telomere. b. centromere. c. long arm of the chromosome. d. None of the other answer options is correct. e. short arm of the chromosome.

b. centromere.

When nonhomologous chromosomes exchange parts, a(n) _____ has occurred. a. mismatch b. reciprocal translocation c. base exclusion d. closed reading frame e. inversion

b. reciprocal translocation

The relatively large number of new mutations that occur in the human genome in each generation is tolerable because: a. most of the mutations occur in somatic cells, not germ cells. b. compared to other organisms, changes in our proteins have relatively little effect on our cells' structures and functions. c. most of our genome is noncoding DNA, so few mutations affect our proteins. d. we have excellent protein repair mechanisms. e. we have excellent DNA repair mechanisms.

c. most of our genome is noncoding DNA, so few mutations affect our proteins.

Which of the following restriction enzymes produce sticky ends? (Select all that apply.) (An arrow indicates the restriction site.) a. AbsI with the restriction sequence 5′- CC↓TCGAGG-3′ b. SspI with the restriction sequence 5′- AAT↓ATT-3′ c. BssKI with the restriction sequence 5′- ↓CCCGGG-3′ d. TaiI with the restriction sequence 5′- ACGT↓ -3′ e. Eco53kl with the restriction sequence 5′- GAG↓CTC-3′

d. TaiI with the restriction sequence 5'-ACGT↓-3'

Which of the following statements applies to frameshift mutations? a. They are known risk factors in most forms of cancer, including breast and colon cancer. b. They are known risk factors in breast cancer, but not colon cancer. c. They cause the insertion or deletion of a single amino acid from the polypeptide chain. d. They change the amino acid sequence downstream from the mutant site. e. They create a premature stop codon at the site of mutation.

d. They change the amino acid sequence downstream from the mutant site.

One method for changing the DNA sequence of a gene in its original location in the cell uses a type of RNA known as: a. TOASTR b. CHANGR c. none of these d. FRYR e. CRISPR

e. CRISPR

Which of the following is considered a transgenic organism? a. a human given a blood-clotting factor produced in bacterial cells b. a fern grown in cell culture from a single fern root cell c. a human treated with insulin produced by bacteria d. a bacterium that has received genes by conjugation e. a rat with rabbit hemoglobin genes

e. a rat with rabbit hemoglobin genes

A chromosomal segment that breaks off and attaches to another chromosome is what type of mutation? a. duplication b. translocation c. inversion d. reciprocal translocation e. deletion

e. deletion

True or false: A silent mutation is a mutation that only occurs in noncoding regions of DNA.

false

True or false: Transformation is the process where DNA is extracted from a plasmid.

false

Organisms that have been modified to contain DNA from other species are known as: (Select all that apply.) a. recombinant DNA organisms b. genetically modified organisms c. DNA hybrids d. Sanger recombinants e. transgenic organisms

transgenic organisms, genetically modified organisms (GMO's).