BIO 340 Exam 2 Prep Questions And Answers
With Verified Solutions Graded A+ Latest Update
2025.
Normal ____________ - bonding interactions between purines and pyrimidines establishes normal
____________ - ____________ base pairs; however, this "normal" pairing is prone to rearrangements due
to the presence of ____________ within the ring structures and this instability can lead to ____________
mutations. - ANSWER hydrogen; Watson-Crick; resonance; point
When it comes to viral genomes, they vary widely. Some carry ____________ while other carry
____________. The length of the genetic material can be as little as ____________ bases ( or base pair)
or as long as ____________ or more. - ANSWER DNA; RNA; a few thousand; 200,000
From completely uncondensed chromosome to "beads-on-a-string", the length is shorted ____________.
From "beads-on-a-string" to the formation of solenoids, the length is shorted again ____________ for a
total of ____________. - ANSWER 6 fold. 7 fold; 42 fold
Do viruses carry single or double stranded genetic material? - ANSWER Both
What proteins are considered nonhistone and what percentage do they make up within chromatin? -
ANSWER Any chromosome associated proteins that aren't part of the nucleosome material and they
make up about 50%
What is the range of genes that a virus can carry and what do most of these genes typically code for? -
ANSWER It codes for roughly 5-300 genes and it typically codes for viral proteins and replication
enzymes
What are the two general ways that a virus accomplishes replication? - ANSWER 1) Lytic
replication and 2)Lysogenic or Latent replication
When the beads-on-a-string formation coil upon themselves they form a ____________ which consist of
about ____________ to ____________ nucleosome bound together and are stabilized by the presence of
____________. By this point, the chromosome is further shortened to about ____________ that of the
beads-on-a-string length. This means that at this point it is roughly ____________ times shorter than the
completely unbound chromosome. Solenoid formation usually occurs during ____________ -
ANSWER solenoid; 6; 8; H1; 1/6; 42; interphase
The third level of condensation is mediated by ____________ ____________ proteins that give
chromosomes their overall shape. - ANSWER nonhistone scaffolding
What structures are responsible for holding bacterial chromosomes in large loops? - ANSWER
Small-nucleoid associated proteins
What structures are responsible for holding bacterial chromosomes in small loops or "V shapes" within
the larger loops? - ANSWER Structural maintenance of chromosome (SMC)
,____________ ____________ contain DNA sequences that encode proteins essential for normal bacterial
functions and metabolism - ANSWER Structural genes
The diameter of one nucleosome is about ____________ and a bundle of nucleosomes creates what is
called a ____________ which is about ____________ in diameter. As these coil up even further, the
resulting structure is then referred to as ____________ which is about ____________ in diameter. -
ANSWER 10 nm; solenoid; 30nm; chromatin; 300nm
____________ ____________ separate one gene from the next. - ANSWER Intergenic regions
__________- ____________ _____________ is the least twisted form of circular chromosome -
ANSWER Open-circle DNA
__________ chromosomes form into loops of __________ to __________ kb that are anchored to the
nonhistone scaffolding proteins at sites called MARs (__________ __________ __________ ). The result
is a fiber known as __________ that is about __________ in diameter - ANSWER Interphase;
20; 100; matrix attachment regions; chromatin; 300nm
Because viruses are infectious ____________, they are considered ____________, which is why they
require a host to "survive". This fact is what makes them ____________ intracellular ____________
although they do carry small ____________ ____________ genomes housed in ____________ material. -
ANSWER particles; noncellular; obligate; parasites; nucleic acid; proteinaceous
____________ occurs in varying degrees, but is the term to describe excessively compact circular DNA
as a result of over or under twisting. - ANSWER Supercoiling
After the ____________ tetramers form and bind nonspecifically to the ____________ grooves of DNA,
more histone ____________ will insert two ____________ dimers into the ____________ tetramer to
form the final nucleosome ____________. Once this is complete, the ____________ are then recycled. -
ANSWER H3-H4; minor; chaperones; H2A-H2B H3-H4; octamer; chaperones
In the final stage of chromosome condensation, the chromatin that is __________ in diameter forms
__________ with the __________ proteins creating a tightly wound __________ in the center. The result
is the diameter expanding to __________ and the length shortening __________ times that of the
previous stage. - ANSWER 300 nm; rosettes; scaffolding; spiral; 700 nm; 250
If action of ____________ is impaired or absent the result will inevitably result in super coiling -
ANSWER topoisomerase
The ____________ replication mechanism is also known as the "active" form because it replicates itself
within a cell countless times over until the cell bursts to release huge numbers of viruses that will repeat
the process. - ANSWER lytic
____________ ____________ are a diverse set of regulatory, enzymatic, and structural elements that
perform chromosome-associated tasks in the nucleus. - ANSWER nonhistone proteins
As chromatin condenses in preparation for cell division, it morphs into a structure called a
____________. One arm of this is about ____________ in diameter, and the two together are not
surprisingly estimated to be about ____________ in diameter - ANSWER chromatid; 700nm;
1400nm
, ____________ ____________ are tens to thousands of times larger than bacterial or archaeal genomes
and typically include genes in the ____________ - ANSWER Eukaryotic genomes; thousands
What do viral genes usually code for? - ANSWER viral proteins and viral replication enzymes
In the dormant form of replication, it is referred to as _____________ in bacterial hosts and
____________ in eukaryotes - ANSWER Lysogenic; latent
____________ are small ____________ or positively charged proteins that tightly bind DNA to form
structures called nucleosomes - ANSWER Histones; basic
Viruses are elegant ____________ ____________ delivery vehicles with a ____________ shell that
surrounds a nucleic acid ____________. In some cases the ____________ shell is further encapsulated by
a ____________ ____________ - ANSWER nucleic acid; protein; genome; protein;
phospholipid bilayer
During nucleosome assembly, first the ____________ sub-units H2A and H2B will form into
____________ and H3 and H4 will do the same. - ANSWER histone ; dimers
What are the components that make up a T4 bacteriophage virus? - ANSWER 1. Head
2. Tail Sheath
3. Tail Fiber
4. DNA ( contained within head)
____________ and ____________ are composed of constitutive ____________ ; they are highly
condensed regions whose state of compaction is relatively constant. - ANSWER Telomeres;
centromeres; heterochromatin
____________ proteins and their associated regions on the DNA can be identified by treating mitotic
chromosomes with special ____________ and ____________ enzymes. - ANSWER
Scaffolding; detergents; restriction
The configuration of a viral genome can either be ___________ stranded, ___________ stranded, as well
as linear or ___________. - ANSWER single; double; circular
In the first step viral replication, the viral particle ____________ to the ____________ of a host cell. -
ANSWER binds; surface
Bacterial genome sizes typically range from about ____________ to ____________ in length -
ANSWER 0.5 to 10 Mb (megabases)
The linking chromosome region is not alone but with the ____________ ____________ subunit. -
ANSWER H1 histone
Most bacteria carry a ____________ chromosome although some species carry multiple copies of the
same ____________. - ANSWER haploid; gene
The intelligence and complexity of an organism is loosely but ____________ related to the number of
genes that an organism possesses. - ANSWER directly
Histones + Chromosome = - ANSWER Core DNA
With Verified Solutions Graded A+ Latest Update
2025.
Normal ____________ - bonding interactions between purines and pyrimidines establishes normal
____________ - ____________ base pairs; however, this "normal" pairing is prone to rearrangements due
to the presence of ____________ within the ring structures and this instability can lead to ____________
mutations. - ANSWER hydrogen; Watson-Crick; resonance; point
When it comes to viral genomes, they vary widely. Some carry ____________ while other carry
____________. The length of the genetic material can be as little as ____________ bases ( or base pair)
or as long as ____________ or more. - ANSWER DNA; RNA; a few thousand; 200,000
From completely uncondensed chromosome to "beads-on-a-string", the length is shorted ____________.
From "beads-on-a-string" to the formation of solenoids, the length is shorted again ____________ for a
total of ____________. - ANSWER 6 fold. 7 fold; 42 fold
Do viruses carry single or double stranded genetic material? - ANSWER Both
What proteins are considered nonhistone and what percentage do they make up within chromatin? -
ANSWER Any chromosome associated proteins that aren't part of the nucleosome material and they
make up about 50%
What is the range of genes that a virus can carry and what do most of these genes typically code for? -
ANSWER It codes for roughly 5-300 genes and it typically codes for viral proteins and replication
enzymes
What are the two general ways that a virus accomplishes replication? - ANSWER 1) Lytic
replication and 2)Lysogenic or Latent replication
When the beads-on-a-string formation coil upon themselves they form a ____________ which consist of
about ____________ to ____________ nucleosome bound together and are stabilized by the presence of
____________. By this point, the chromosome is further shortened to about ____________ that of the
beads-on-a-string length. This means that at this point it is roughly ____________ times shorter than the
completely unbound chromosome. Solenoid formation usually occurs during ____________ -
ANSWER solenoid; 6; 8; H1; 1/6; 42; interphase
The third level of condensation is mediated by ____________ ____________ proteins that give
chromosomes their overall shape. - ANSWER nonhistone scaffolding
What structures are responsible for holding bacterial chromosomes in large loops? - ANSWER
Small-nucleoid associated proteins
What structures are responsible for holding bacterial chromosomes in small loops or "V shapes" within
the larger loops? - ANSWER Structural maintenance of chromosome (SMC)
,____________ ____________ contain DNA sequences that encode proteins essential for normal bacterial
functions and metabolism - ANSWER Structural genes
The diameter of one nucleosome is about ____________ and a bundle of nucleosomes creates what is
called a ____________ which is about ____________ in diameter. As these coil up even further, the
resulting structure is then referred to as ____________ which is about ____________ in diameter. -
ANSWER 10 nm; solenoid; 30nm; chromatin; 300nm
____________ ____________ separate one gene from the next. - ANSWER Intergenic regions
__________- ____________ _____________ is the least twisted form of circular chromosome -
ANSWER Open-circle DNA
__________ chromosomes form into loops of __________ to __________ kb that are anchored to the
nonhistone scaffolding proteins at sites called MARs (__________ __________ __________ ). The result
is a fiber known as __________ that is about __________ in diameter - ANSWER Interphase;
20; 100; matrix attachment regions; chromatin; 300nm
Because viruses are infectious ____________, they are considered ____________, which is why they
require a host to "survive". This fact is what makes them ____________ intracellular ____________
although they do carry small ____________ ____________ genomes housed in ____________ material. -
ANSWER particles; noncellular; obligate; parasites; nucleic acid; proteinaceous
____________ occurs in varying degrees, but is the term to describe excessively compact circular DNA
as a result of over or under twisting. - ANSWER Supercoiling
After the ____________ tetramers form and bind nonspecifically to the ____________ grooves of DNA,
more histone ____________ will insert two ____________ dimers into the ____________ tetramer to
form the final nucleosome ____________. Once this is complete, the ____________ are then recycled. -
ANSWER H3-H4; minor; chaperones; H2A-H2B H3-H4; octamer; chaperones
In the final stage of chromosome condensation, the chromatin that is __________ in diameter forms
__________ with the __________ proteins creating a tightly wound __________ in the center. The result
is the diameter expanding to __________ and the length shortening __________ times that of the
previous stage. - ANSWER 300 nm; rosettes; scaffolding; spiral; 700 nm; 250
If action of ____________ is impaired or absent the result will inevitably result in super coiling -
ANSWER topoisomerase
The ____________ replication mechanism is also known as the "active" form because it replicates itself
within a cell countless times over until the cell bursts to release huge numbers of viruses that will repeat
the process. - ANSWER lytic
____________ ____________ are a diverse set of regulatory, enzymatic, and structural elements that
perform chromosome-associated tasks in the nucleus. - ANSWER nonhistone proteins
As chromatin condenses in preparation for cell division, it morphs into a structure called a
____________. One arm of this is about ____________ in diameter, and the two together are not
surprisingly estimated to be about ____________ in diameter - ANSWER chromatid; 700nm;
1400nm
, ____________ ____________ are tens to thousands of times larger than bacterial or archaeal genomes
and typically include genes in the ____________ - ANSWER Eukaryotic genomes; thousands
What do viral genes usually code for? - ANSWER viral proteins and viral replication enzymes
In the dormant form of replication, it is referred to as _____________ in bacterial hosts and
____________ in eukaryotes - ANSWER Lysogenic; latent
____________ are small ____________ or positively charged proteins that tightly bind DNA to form
structures called nucleosomes - ANSWER Histones; basic
Viruses are elegant ____________ ____________ delivery vehicles with a ____________ shell that
surrounds a nucleic acid ____________. In some cases the ____________ shell is further encapsulated by
a ____________ ____________ - ANSWER nucleic acid; protein; genome; protein;
phospholipid bilayer
During nucleosome assembly, first the ____________ sub-units H2A and H2B will form into
____________ and H3 and H4 will do the same. - ANSWER histone ; dimers
What are the components that make up a T4 bacteriophage virus? - ANSWER 1. Head
2. Tail Sheath
3. Tail Fiber
4. DNA ( contained within head)
____________ and ____________ are composed of constitutive ____________ ; they are highly
condensed regions whose state of compaction is relatively constant. - ANSWER Telomeres;
centromeres; heterochromatin
____________ proteins and their associated regions on the DNA can be identified by treating mitotic
chromosomes with special ____________ and ____________ enzymes. - ANSWER
Scaffolding; detergents; restriction
The configuration of a viral genome can either be ___________ stranded, ___________ stranded, as well
as linear or ___________. - ANSWER single; double; circular
In the first step viral replication, the viral particle ____________ to the ____________ of a host cell. -
ANSWER binds; surface
Bacterial genome sizes typically range from about ____________ to ____________ in length -
ANSWER 0.5 to 10 Mb (megabases)
The linking chromosome region is not alone but with the ____________ ____________ subunit. -
ANSWER H1 histone
Most bacteria carry a ____________ chromosome although some species carry multiple copies of the
same ____________. - ANSWER haploid; gene
The intelligence and complexity of an organism is loosely but ____________ related to the number of
genes that an organism possesses. - ANSWER directly
Histones + Chromosome = - ANSWER Core DNA
