biology: DNA and replication 9 weeks test review
if 30% of the nitrogen bases in a sample of DNA are guanine, what percentage of the bases will be adenine?
20%.
if a section of DNA had the following nitrogen base sequence, TACGCATTG, the sequence complimentary to this would be...
ATGCGTAAC.
if a DNA strand had the sequence TACGCATAT, the DNA strand complimentary to that would be ______________.
ATGCGTATA.
the main enzyme of replication whose function is to link together the individual nucleotides along a template strand is called...
DNA polymerase.
what enzyme is responsible for proofreading newly formed DNA strands?
DNA polymerase.
which of the following would not be found in a nucleotide?
DNA polymerase.
when replication is complete, two identical copies of the DNA molecule have been produced and the cell is ready to begin ___________.
cell division.
each strand of the DNA molecule can be used to make another strand during replication. this is because the two sides are _________ to each other.
complimentary.
the sugars are bonded to the phosphates in DNA molecule by:
covalent bonding.
two nucleotides are held together in a DNA molecule by which of the following types of bonds?
covalent bonds.
which one of the following would be a nucleotide that could be found in a DNA molecule?
deoxyribose + phosphate group + cytosine
what is the name of the 5-carbon sugar found in DNA?
deoxyribose.
the result of replication is two DNA molecules:
each with one new strand and one original strand.
DNA that has become damaged may be repaired by:
enzymes.
the DNA in eukaryotes is different than the DNA in prokaryotes. which one of the following is true of eukaryotic DNA?
eukaryotic DNA is contained inside a nucleus; eukaryotic chromosomes consist of individual, separate chromosomes; eukaryotic DNA has many more base pairs than prokaryotic DNA.
what might cause accidental damage or changes in existing DNA?
exposure to chemicals; radioactivity; x-rays; excessive exposure to ultraviolet light.
which nitrogen base forms a bond with cytosine?
guanine.
enzymes that are responsible for untwisting and separating the two DNA strands during the copying process are called...
helicases.
nitrogen bases are held together across the center of the helix by which type of bond?
hydrogen bonds.
a molecule of DNA does not...
include fats or lipids.
which of the following does not describe the structure of DNA?
it contains the 5-carbon sugar, ribose.
what is the function of DNA in cells?
it stores the information that directs the ribosomes in protein synthesis.
a change in the base sequence of DNA is called what?
mutation.
the sequence of ________ carries the genetic information of an organism.
nitrogen bases.
the information that directs protein synthesis is in DNA's...
nitrogenous bases.
when DNA is damaged inside a cell, enzymes called ________ can cut out and remove the damaged sections.
nucleases.
in what part of the cell does replication occur?
nucleus.
both DNA and RNA contain...
phosphate groups.
a class of organic compounds that consists of double-ringed structures with alternating nitrogen and carbon atoms would be called:
purines.
during replication, the two sides of the DNA molecule separate, creating ________ which are the places where the new nucleotides are added.
replication fork.
the "Y" shaped region where the nucleotides are being added during replication is known as a...
replication fork.
the process by which DNA makes an exact copy of itself is called...
replication.
the watson-crick model suggested that _________ could carry coded information.
sequence of bases.
hydrogen bonding plays an important role in the DNA structure by joining together:
the 2 hydrogen strands (sides) of the DNA helix.
the rules of complimentary base pairing link together which of the following?
two nitrogen bases.
which of the following bases is never found in DNA?
uracil.
tha sequence of DNA "backbone" is ______________.
—phosphate-sugar-phosphate-sugar
