Chapter 12 DNA replication
week 14
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____ 1. DNA replication results in two DNA molecules,
a. each with two new strands.
b. one with two new strands and the other with two original strands.
c. each with one new strand and one original strand.
d. each with two original strands.
____
2. During DNA replication, a DNA strand that has the bases CTAGGT produces a strand with
the bases
a. TCGAAC.
b. GATCCA.
c. AGCTTG.
d. GAUCCA.
____
3. What enzyme works to add DNA to ends of chromosomes in rapidly dividing cells such as
those found in an embryo, to prevent genes from being lost during replication?
a. DNA polymerase
b. histones
c. telomerase
d. chromatin
____
4. Which of the following include all the others?
a. DNA molecules
b. histones
c. chromosomes
d. nucleosomes
Figure 12–1
____
5. In Figure 12–1, what nucleotide is going to be added at point 1, opposite from thymine?
a. adenine
b. thymine
c. cytosine
d. guanine
____
6. In Figure 12–1, what is adding base pairs to the strand?
a. histones
b. nucleosomes
c. DNA polymerase
d. chromatin
____
7. In eukaryotes, DNA
a. is located in the nucleus.
b. floats freely in the cytoplasm.
c. is located in the ribosomes.
d. is circular.
____
8. Which would be greater in a eukaryote than in a prokaryote?
a. The percentage of guanine nucleotides.
b. The total number of base pairs in a chromosome.
c. The number of replication forks on a strand of DNA.
d. The total amount of DNA in a cell.
____
9. What binds to the prokaryotic chromosome to start DNA replication?
a. replication forks
b. regulatory proteins
c. chromatids
d. telomeres
____ 10. In both prokaryotes and eukaryotes, how many copies of the chromosome are left after
replication?
a. 1
b. 2
c. 3
d. 4
____ 11. In both prokaryotes and eukaryotes, DNA replication happens
a. before cell division.
b. in the nucleus.
c. only to telomeres.
d. around the histones.
Modified True/False
Indicate whether the statement is true or false. If false, change the identified word or phrase to make the
statement true.
____ 1. The replication of a DNA molecule results in four copies of the same gene.
_________________________
____
2. DNA is tightly wrapped around nucleosomes. _________________________
____
3. A DNA strand that had the sequence TACGTT would have a complimentary strand
ATCGAT.
____
4. In eukaryotes, DNA replication proceeds in one direction along the DNA molecule.
_________________________
Completion
Complete each statement.
1. The tips of chromosomes are known as _________________________.
2. A prokaryotic cell replicates its _________________________ before it splits to form new
cells, so that each new cell can have genetic material.
3. Eukaryotic DNA has more replication forks than prokaryotic DNA, because it has more
starting places, or _________________________.
Short Answer
1. During DNA replication, what two processes must occur before the two strands of a DNA
molecule can separate?
2. Identify and explain the role of the molecule, represented by the spheres in Figure 12–2.
Figure 12–2