Final Dna Sequencing Test Bank Answers Chapter 9

Chapter 9: DNA Sequencing

Multiple Choice

1. In the Sanger sequencing method, which of the following, when incorporated into the growing strand, are used to determine the identity of the base at a particular position in a piece of DNA?

A. Ribonucleotides

B. Deoxyribonucleotides

C. Dideoxyribonucleotides

D. Amino acids

OBJ: 9.1

2. The ddNTP:dNTP ratio is too high (too much ddNTP). How will this effect the sequencing results?

A. No effect

B. A sequencing ladder of only short fragments

C. A sequencing ladder of only long fragments

D. Equally spaced bands in every lane

OBJ: 9.1

3. Which of the following is included in sequencing reactions to deter secondary structure in the template and synthesized fragments?

A. Deaza-GTP

B. Manganese

C. Magnesium

D. extra dNTP

OBJ: 9.1

4. The DNA fragments in the bands seen in the lane corresponding to the sequencing reaction in which dideoxycytidine was added all end with which of the following nucleotides?

A. A

B. C

C. T

D. G

OBJ: 9.3

5. Which end of the sequenced DNA is found at the bottom of a sequencing gel?

A. 5'

B. 3'

C. 2'

D. 1'

OBJ: 9.3

6. In Sanger sequencing, bands that are present in lanes from the tube containing ddCTP are read as which of the following nucleotides?

A. A

B. T

C. C

D. G

OBJ: 9.3

7. In Sanger sequencing, co-migrating bands in the ddATP and ddGTP are interpreted as which of the following nucleotides?

A. R

B. A

C. C

D. G

OBJ: 9.3

8. Sequencing gels are read in which of the following directions?

A. Top to bottom

B. Bottom to top

C. Across lanes

D. Diagonally

OBJ: 9.3

9. Cycle sequencing was made possible through the development of what type of reagent?

A. Fluorescent dyes

B. dITP

C. Labeled primers

D. Heat-stable polymerases

OBJ: 9.1

10. A portion of a sequencing gel is described as follows: the first band at the bottom of the gel was in the ddATP lane; the next band going up the gel was in the ddTTP lane, then the ddCTP lane, the ddGTP lane, the ddATP lane, the ddTTP lane, the ddCTP lane, the ddCTP lane, the ddATP lane, and the ddGTP lane. Which of the following is the correct sequence as determined on this gel?

A. 5'GACCTAGCTA3'

B. 3'ATCGATCCAG5'

C. 5'ATCGATCCAG3'

D. 3'TCAGTCAGC5'

OBJ: 9.3

11. A Sanger sequencing procedure has been performed on a 300-bp piece of DNA. When the fragments were run on the gel, there were bands distributed throughout the lanes corresponding to ddTTP, ddCTP, and ddATP. In the ddGTP lane, there was one thick band at the bottom of the gel. What is the interpretation of these results?

A. No dGTP was added to the reaction mix.

B. No ddGTP was added to the reaction mix.

C. There was only one G in the whole 300-bp piece of DNA.

D. The 300-bp piece of DNA contained Gs only.

OBJ: 9.3

12. Incomplete cleaning of the fluorescently labeled sequencing ladder will result in what effect?

A. Dim bands or peaks

B. Unequal signal from lane to lane

C. Dye blobs

D. Equally spaced bands in every lane

OBJ: 9.3

13. Which is the output from capillary electrophoresis of a fluorescent sequence ladder?

A. Autoradiogram

B. Electropherogram

C. Pictogram

D. Nomogram

OBJ: 9.2

14. Dye terminator sequencing has been performed using capillary electrophoresis to separate the fragments. ddATP has been labeled with a “green” fluor, ddTTP with “red,” ddCTP with “blue,” and ddGTP with “black.” The colors are detected in the following order: red, green, black, red, green, blue, red, black, black, green, blue. What is the sequence of this fragment?

A. TCGTCATGGAC

B. GCTACGTAATG

C. CAGGTCATGAT

D. TAGTACTGGAC

OBJ: 9.3

15. Which of the following is the most widely used method of DNA sequencing in clinical laboratories today?

A. Pyrosequencing

B. Maxam–Gilbert sequencing

C. Sanger sequencing

D. Array sequencing

OBJ: 9.4

16. A pyrosequencer detects visible light, making it which type of instrument?

A. Luminometer

B. UV spectrometer

C. Mass spectrometer

D. Fluorometer

OBJ: 9.4

17. When a sequence is entered and compared with all other sequences in a database, which of the following is being performed?

A. Algorithm

B. Query

C. Motif

D. Annotation

OBJ: 9.8

18. An analysis that takes place in silico is happening in which of the following places?

A. Computer

B. Laboratory

C. Biological organism

D. Tissue

OBJ: 9.8

19. What is generated when a sample sequence is compared to a normal reference sequence?

A. Base call

B. Query

C. Variant call

D. Library

OBJ: 9.8

20. What is the purpose of indexing?

A. Sequencing quality control

B. Sample identification

C. Sequence alignment

D. Variant calling

OBJ: 9.8

21. A segment of DNA has been sequenced and noted as the following: AYATRCG. Which of the following is the correct interpretation of this notation?

A. A, C/T, A, T, A/G, CG

B. A, G/T, A, T, C/G, CG

C. A, T, A, T, A/G, CG

D. A, C/T, A, T, A/T, CG

OBJ: 9.8

22. Ten equivalents of a genome were cut into small pieces and sequenced. Computers were then used to put the sequence of the pieces together to determine the sequence of the intact genome. The method described is which of the following?

A. Basic local alignment search tool

B. Hierarchal shotgun sequencing

C. Whole-genome shotgun sequencing

D. Filtering and annotation

OBJ: 9.10

23. Which of the following pieces of information has been determined about the human genome?

A. Chromosome 13 has the most genes per base pair.

B. The size of the human genome is 10.6 Gbp.

C. The average gene size is 45 kbp.

D. Chromosome X has the fewest GC base pairs.

OBJ: 9.9

24. The goal of the HapMap project was which of the following?

A. To find blocks of SNPs that are inherited together

B. To complete the human genome sequence

C. To compare human and primate genomes

D. To sequence all bacterial genomes

OBJ: 9.9

25. The genetic sequence database sponsored by the National Institutes of Health was originally named what?

A. PubMed

B. GenBank

C. SwissProt

D. SeqScape

OBJ: 9.9

26. What is the first step in a primer-based targeted library preparation?

A. Hybridization

B. Amplification

C. Enzyme digestion

D. Pooling

OBJ: 9.7

27. What is the first step in a probe-based targeted library preparation?

A. Hybridization

B. Pooling

C. Enzyme digestion

D. Amplification

OBJ: 9.7

28. What is the first step in library preparation for whole-genome sequencing?

A. Hybridization

B. Pooling

C. Fragmentation

D. Amplification

OBJ: 9.7

29. Which next-generation sequencing (NGS) method produces fluorescent signals from immobilized templates made by bridge PCR?

A. Ion conductance

B. Reversible dye terminator

C. Pyrosequencing

D. Single-molecule sequencing

OBJ: 9.5

30. Which NGS method produces sequences from changes in pH?

A. Reversible dye terminator

B. Maxam–Gilbert sequencing

C. Ion conductance

D. Pyrosequencing

OBJ: 9.5