genetics test retake
5ʹ RNA nucleotides, DNA nucleotides 3ʹ
An Okazaki fragment has which of the following arrangements?
the amount of A is always equivalent to T, and C to G
Chargaff's analysis of the relative base composition of DNA was significant because he was able to show that
12%
Cytosine makes up 38% of the nucleotides in a sample of DNA from an organism. Approximately, what percentage of the nucleotides in this sample will be thymine?
Gaps left at the 5ʹ end of the lagging strand because of the need for a 3ʹ onto which nucleotides can attach
Eukaryotic telomeres replicate differently than the rest of the chromosome. This is a consequence of which of the following?
A + C = G + T
In an analysis of the nucleotide composition of DNA, which of the following will be found?
Prokaryotic chromosomes have a single origin of replication, whereas eukaryotic chromosomes have many
Replication in prokaryotes differs from replication in eukaryotes for which of these reasons?
that the critical function of telomeres must be maintained
The DNA of telomeres has been found to be highly conserved throughout the evolution of eukaryotes. What does this most probably reflect?
the leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction.
The leading and the lagging strands differ in that
endonuclease, DNA polymerase I, DNA ligase
To repair a thymine dimmer by nucleotide excision repair, in which order do the necessary enzymes act?
the nucleotide sequence of the template strand
What determines the nucleotide sequence of the newly synthesized strand during DNA replication?
he 5ʹ to 3ʹ direction of one strand runs counter to the 5ʹ to 3ʹ direction of the other strand
What is meant by the description ʺantiparallelʺ regarding the strands that make up DNA?
to add nucleotides to the end of a growing DNA strand
What is the function of DNA polymerase III?
join Okazaki fragments together
What is the role of DNA ligase in the elongation of the lagging strand during DNA replication?
hydrogen
What kind of chemical bond is found between paired bases of the DNA double helix?
DNA polymerase III
Which enzyme catalyzes the elongation of a DNA strand in the 5ʹ → 3ʹ direction?
the diameter of the helix
Which of the following can be determined directly from X-ray diffraction photographs of crystallized DNA?
ligase
Which of the following covalently connects segments of DNA?
single-strand binding proteins
Which of the following help to hold the DNA strands apart while they are being replicated?
DNA polymerase I
Which of the following removes the RNA nucleotides from the primer and adds equivalent DNA nucleotides to the 3ʹ end of Okazaki fragments?
helicase
Which of the following separates the DNA strands during replication?
primase
Which of the following synthesizes short segments of RNA?
Purines pair with pyrimidine
Why does the DNA double helix have a uniform diameter?
histones
in a nucleosome, the DNA is wrapped around