CHAPTER 16 PRACTICE QUESTIONS WITH KEY Online
quizzes with key
http://www.funtrivia.com/playquiz/quiz18993515bfd10.html
http://highered.mcgrawhill.com/sites/0072507470/student_view0/chapter3/animation__dna_replication__quiz_1_.html
1. DNA is a polymer of
a. Nucleotides b. Fatty Acids
c. Deoxyribose sugar
d. Double helices
2. Pyrmidines include
a. Adenine and cytosine b. adenine and guanine c. cytosine and thymine d. cytosine and
guanine
3. For double-stranded DNA, consider the following base ratios:
1. A/G
2. C/T
3. C/G
4. (A+C)/(G+T)
5. (A+G)/(C+T)
6. (A+T)/(G+C)
Which of these ratios always equals 1?
a. 1 and 2 b. 4 and 6 c. 3, 4, 5 d. 1, 4, 5 e. 3 and 6
4. The 2 nucleotide polymer chains in DNA are
a. Semiconservative b. parallel c. continuous d. antiparallel
5. In the Mesleson-Stahl experiment, which model of DNA replication was NOT eliminated?
a. Semiconservative
b. Dispersive
c. Conservative
6. List the sequence complementary to 5’ CCTAGGGTC 3’
7. The % of cytosine in double stranded DNA is 24%. What is the % of thymine in the DNA?
8. The enzymes that break hydrogen bonds between DNA strands are:
a. Polymerases b. Catalases c. Helicases d. strandases
9. DNA replication results in
a. 2 completely new strands of DNA b. 1 new molecule of RNA c. 2 strands which
each contain 1 original strand d. a double stranded molecule with sections of old and
sections of new DNA
10. A stretch of a chromosome that encodes a protein is called a:
a. Base pair b. gene c. chromatid d. replicon
11. Two separate DNA strands are held together by:
a. Covalent bonds
b. sugar and phosphate backbone c. ligase d. hydrogen
bonds
12. Before DNA polymerase can synthesize new DNA:
a. Topoisomerase must relieve physical stress in the double helix
b. An RNA primer must be made by primase
c. Single stranded binding protein must hold the two strands apart
d. DNA nucleotides must assemble into a polymer
13. Identification of DNA as a helical structure was made by:
a. Franklin b. Chargaff c. Morgan d. Mendel
14. Enzymes called ____ catalyze the formation of covalent bonds that hold together the sugarphosphate backbone of the DNA molecule
a. Helicases b. primases c. topoisomerases d. ligases
15. If DNA polymerase could add bases in the 3' to 5' direction, there would be no need for:
a. Okazaki fragments b. Primase c. An origin of replication d. Enzymes
16. The type of DNA synthesis that produces Okazaki fragments is called:
a. Helical d. Semiconservative c. Discontinuous d. Fancy
17. Where does DNA replication take place in human cells?
a. In the cytoplasm b. On ribosomes c. In the cell membrane d. In the nucleus
True or False
18. __Watson and Crick devised the experiment to suggest that DNA replication is semi-conservative.
19.__The DNA has a beta-pleated structure.
20.__The lagging strand is built in the 3’ to 5’ direction.
21.__DNA Polymerase joins together Okazaki Fragments.
22.__ Meselson and Stahl conducted their experiment using isotopes of carbon.
23.__Single stranded binding proteins are used to join DNA strands back together.
24. Label 1 - 8
b.
i.
Answer key 1. A 2. C 3. C 4. D 5. A 6. 3’ GGATCCCAG 5’ 7. 26 8. C 9. C
10. B 11. D 12. B 13. A 14. D 15. A 16. C 17. D 18. F not Watson and Crick’s
work 19. F 20. F DNA can only be synthesized 5”  3’ 21. F DNA polymerase synthesizes
DNA 22. They did not use carbon 23. F SSB holds DNA strands apart 24.
1 = SSB 2 = Sugar phosphate backbone of original/parental DNA strand 3 =new double
stranded DNA 4 = location at which ligase will seal the sugar phosphate backbone of 2 Okazaki
fragments 5 = replication fork and location at which helicase operates 6 = template strands of
original DNA molecule 7 = Continouous DNA replication at leading strand 8 = Okazaki
fragments of lagging strand, discontinouous DNA replication