Ch 9 Flashcards
In order for the genetic material to fulfill its role in cells, it must meet which of the following criteria?
variation
replication
information
transmission
The capsule present on Streptococcus pneumoniae
prevents the immune system from killing the organism
Injection of which of the following in Griffith’s experiments would cause the death of mice?
- dead smooth bacteria + live rough bacteria
- live smooth bacteria + live rough bacteria
- live smooth bacteria
In the Avery, McLeod and McCarty experiment, which of the following mixtures would yield smooth colonies when plated?
- Type R bacteria + type S DNA extract
- Type R bacteria + type S DNA extract + RNase
- Type R bacteria + type S DNA extract + protease
Avery, McLeod, and McCarty demonstrated that only purified
DNA can convert type R bacteria into type S.
For a molecule to serve as the genetic material, it must meet the following key criteria: information,
variation
replication
information
transmission
The two nucleic acids are
RNA and DNA
The appearance of colonies of Streptococcus pneumoniae is related to the presence or absence of
capsules
If a mouse died after infection with Streptococcus pneumoniae, Griffith would be able to find what type of bacteria in its blood?
smooth live
Rank the five levels of structural features of DNA. Start at the top with the most complex (or largest), and end at the bottom with the least complex (or smallest).
Genome chromosome double helix strand of DNA nucleotides
What statement best describes the results of the Avery, McLeod, and McCarty experiment that show DNA causes transformation in Streptococcus pneumoniae?
S. pneumoniae DNA degraded chemically does not cause transformation.
Avery, McLeod, and McCarty used established biochemical procedures to purify macromolecules from the type S streptococci. They found out that R bacteria can only be transformed by what type of purified macromolecul
DNA
The components of a nucleotide are
5-carbon sugar, a phosphate group and a nitrogenous base.
Which are nucleic acids?
RNA and DNa
The 5 prime end of a DNA strand has a ___ group
phosphate
The 3 prime end has a
_______ group
hydroxyl
Which structural features of DNA, which has the highest level of complexity?
Genome
DNA, adenine normally pairs with ____ and cytosine normally pairs wit ______
thymine , guanine
A segment of DNA has the sequence 5’-ATGCTT-3’. The complementary sequence would be
3’-TACGAA-5’
Which end of one strand of DNA within a double helix is next to the 5’ end of the other strand within that helix?
The 3’ end
Watson and Crick proposed that the structure of DNA is a double helix in which the DNA strands are ________ and obey the ________ rule.
antiparallel; AT/GC
If a strand of DNA has a T nucleotide, the complementary strand will have which nucleotide paired with the T?
A
During what process are parental DNA strands used as templates for the synthesis of new DNA strands
DNA replication
In a DNA double helix, one strand runs in one direction, while the other is upside down relative to the first one. This characteristic describes the
antiparallel
The proposed models for DNA replication included
dispersive replication
semiconservative replication
conservative replication
Rosalind Franklin, a British biophysicist, analyzed DNA using X- ____ ______________techniques, and proposed that the molecule had a helical structure with a uniform diameter.
X-ray diffraction
The semiconservative mechanism of DNA replication produces
two molecules each with a parental strand and a daughter strand
Erwin Chargaff showed that
the amounts of A/T and C/G are equal
The primary purpose of the Meselson-Stahl experiment was to determine the
Multiple choice question.
mechanism of DNA replication
Which are properties of the DNA double helix proposed by Watson and Crick?
The DNA strands are antiparallel
The DNA strands obey the AT/GC rule
The model organism used by Meselson and Stahl was
Escherichia coli
In DNA replication, the strands on the original molecule are used as ______ for the synthesis of new DNA strands
templates
A Meselson-Stahl experiment is performed on a bacterial culture. What percentage of DNA molecules is expected to be of intermediate density after three rounds of replication?
25%
Three different models for the mechanism of DNA replication have been proposed. These are
semi-conservative, conservative, and dispersive.
The DNA strands that can be copied to produce new DNA strands are called the
template strands.
As a result of the mechanism of DNA replication, the new double-stranded DNA contains one parental strand and one daughter strand.
semiconservative
______________________ and _____________________ performed an experiment that demonstrated the semiconservative mechanism of DNA replication. (LAST NAMES ONLY PLEASE)
Meselson, Stahl
During DNA synthesis, the sites where the two template strands are unwound and new DNA is made are called what?
Replication forks
Meselson and Stahl used two isotopes of the _____ element in their DNA replication experiments, so that the daughter strands could be distinguished from the parental strands.
Nitrogen
During replication, the enzyme DNA uses energy from ATP to separate the two strands. This generates additional coiling ahead of the replication fork that is alleviated by another enzyme called DNA .
helicase and gyrase or ( topoisomerase)
Assuming DNA replication had been conservative, Meselson and Stahl would have observed what bands in the centrifuge tube after one round of replication?
Two bands: one heavy and one light
The enzyme responsible for covalently linking nucleotides together to form DNA strands is called DNA
polymerase
During DNA replication, the parental DNA strand can also be called a(n) ______________ strand, because it is used for the synthesis of a daughter strand of DNA.
template
template
Which enzyme is required to initiate DNA synthesis on a bare template strand?
Primase
DNA replication proceeds outward from two___ , which are the sites where the template strands are unwound and new DNA is synthesized
replication forks
Which are enzymatic features of DNA polymerase?
- It can only synthesize DNA in the 5’ to 3’ direction
* It is unable to begin DNA synthesis on a bare template strand
helicase
causes DNA strand separation at the origin of replication
topoisomerase
Choice, relieves coiling in DNA strands ahead of the replication forkrelieves coiling in DNA strands ahead of the replication fork
single-strand binding protein
prevents the two DNA template strands from re-forming the double helix
The enzyme DNA covalently links nucleotides to synthesize new DNA strands together during DNA replication.
polymerase
Which of the following statements about DNA replication is TRUE?
The leading strand is synthesized continuously while the lagging strand is synthesized in a series of small fragments that are later connected
Which of the following statements about DNA replication is TRUE?
The leading strand is synthesized continuously while the lagging strand is synthesized in a series of small fragments that are later connected
The enzyme DNA
______,,is needed to begin DNA synthesis on a bare template strand. This enzyme makes a short segment of
____ called a primer that is complementary to a DNA sequence on the template strand.
Primase and RNA
Once synthesis has begun, DNA can only be synthesized in a _______ directionv
5’ to 3’
In order to fit into cells, DNA must be
compacted
A nucleosome consists of a core of
eight histone proteins: two each of H2A, H2B, H3, and H4
The 30-nm fiber is comprised of units organized into a more compact structure.
Nucleosome
hich of the following helps explain the remarkably high fidelity for DNA replication?
- The hydrogen bonding between AT and CG pairs is more stable than between mismatched pairs
- DNA polymerase can identify and repair
mismatched nucleotides - DNA polymerase is unlikely to catalyze bond formation between adjacent nucleotides if a mismatched base pair is formed
Heterochromatin involves a tighter packing of loops as compared to
euchromatin
Which enzyme is required to initiate DNA synthesis on a bare template strand?
Primase
DNA must be compacted in order to
fit in cells
When cells prepare to divide, the chromosomes become ______ to aid in proper alignment.
condensed
A nucleosome is composed of ___ or ____ base pairs of DNA wrapped around a core of eight histone proteins called a histone octamer.
146 or 147
Nucleosomes are organized into a more compact structure known as the ________ with the help of the histone protein __
30-nm fiber ; H1
The difference between euchromatin and heterochromatin relates to the
compaction level of the molecule
The enzyme DNA is needed to begin DNA synthesis on a bare template strand. This enzyme makes a short segment of called a primer that is complementary to a DNA sequence on the template strand.
Listen to the complete question
primase; RNA
A metaphase chromosome is ______ a chromosome in a non-dividing cell.
more condensed than
