chapter 12 multiple choice bio
How is a bacterial chromosome replicated?
The circular DNA molecule is replicated from one origin of replication bidirectionally.
demonstrated that DNA is replicated semiconservatively
messelson and stahl
grew bacteria in the presence of heavy nitrogen (15N), followed by growth 14N medium for one or two generations, then measured the density of the DNA
messelson and stahl
Because a newly synthesized DNA molecule contains ____, the replication process is said to be semiconservative.
one parental strand and one new strand
The ends of eukaryotic chromosomes can be lengthened by:
telomerase.
From the DNA X-ray crystallography data, Franklin and Wilkins inferred that ____ while Watson and Crick determined that ____.
the flat nucleotide bases are stacked upon each other; DNA is helical.
Which of the following statements concerning DNA is FALSE?
the sugar present in dna is ribose
Errors in DNA replication can come from:
the sun's UV radiation.
produces breaks in the DNA molecules and then rejoins the strands to prevent supercoiling
topoisomerase
Adenine and thymine are held together by TWO hydrogen bonds in a double stranded DNA molecule.
true
Before the 1940s, scientists believed that proteins, rather than DNA, were the carriers of genetic material in the cell. Why?
twenty different amino acids could produce a large number of unique combinations
In the experiments of Griffith, the conversion of nonlethal R-strain bacteria to lethal S-strain bacteria:
was due to transformation
A replication fork is:
a Y-shaped structure where parental DNA strands are separated by helicase.
discovered that DNA was responsible for bacterial transformation
avery
Which of the following nucleotide sequences represents the complement to the DNA strand 5′ − AGATCCG- 3′?
3′ − TCTAGGC- 5′
The bacteriophages used in Alfred Hershey's and Martha Chase's experiments showed that:
DNA was injected into bacteria
How are eukaryotic chromosomes replicated?
The linear DNA molecules are replicated from multiple origins of replication bidirectionally.
Which of the following statements is FALSE with regard to DNA replication?
The strand being copied is read in the 5'->3' direction.
What allows each strand of DNA to serve as a template for a new DNA strand during replication?
complementary base pairing between purines and pyrimidines on opposite strands
_____ bonds link the sugar and phosphate groups in the backbones of DNA molecules.
covalent phosphodiester
Hydrogen bonds can form between guanine and ____, and between adenine and ____.
cytosine , thymine
The two strands of a DNA double helix can be described as running PARALLEL to each other.
false- anti parallel
In DNA replication, the lagging strand:
is synthesized as a series of Okazaki fragments.
The DNA strand that is replicated smoothly and continuously is called the:
leading strand.
The chemical group in box 5 of the accompanying figure is a:(has diagram attached)
phosphate
prevents formation of hydrogen bonds between complementary base pairs
single strand binding protein
prevents the hydrolysis of single DNA strands by nucleases
single strand binding protein
According to Chargaff's rules:
the adenine content in dna is always equal to the thymine content
____, the ends of eukaryotic chromosomes, shorten with every cell division.
. Telomeres
Which of the following causes the unwinding of the DNA double helix?
DNA helicase
opens the double helix like a zipper
DNA primase
binds DNA at the origin of replication and breaks the hydrogen bonds between the paired bases
DNA helicase
catalyzes the synthesis of an RNA primer at both leading and lagging strand
DNA helicase
catalyzes a reaction that occurs in the lagging strand but not in the leading strand
DNA ligase
catalyzes formation of sugar-phosphate bonds in adjacent Okazaki fragments
DNA ligase
Okazaki fragments are joined together by:
DNA ligase.
adds nucleotides only to the 3' end of an existing polynucleotide strand
DNA polymearse
joins successive nucleotides to a growing polynucleotide strand, complementary to the template strand
DNA polymearse
When a mutation occurs during DNA replication, ____ replaces the incorrect nucleotide with the correct one after the mismatched nucleotide has been removed.
DNA polymerase
Which of the following adds new nucleotides to a growing DNA chain?
DNA polymerase
demonstrated that genetic traits can be transferred from one bacterium to another
Griffith
discovered that the genetic material in bacteriophages is DNA
Hershey and chase
used proteins labeled with 35S and DNA labeled with 32P to demonstrate that viral DNA entered bacterial cells, but viral proteins did not
Hershey and chase
demonstrated the ratio of nucleotide bases in DNA
chargaff
An RNA primer is synthesized by RNA PRIMASE.
false DNA primase
Okazaki fragments are found in the LEADING strand of DNA.
false lagging
One of the PYRIMIDINE bases in a DNA molecule is adenine.
false- purine
the process of DNA replication is CONSERVATIVE
false- semiconservative
X-ray diffraction images produced by ____ were used by Watson and Crick to infer the structure of DNA
franklin
Why is DNA able to store large amounts of information?
its nucleotides can be arranged in a large number of possible sequences