NR507 Midterm Exam Questions And
Answers
Epigenetics - Answers-heritable alterations that are not due to changes in DNA
sequence
.epigenetic modifications, or "tags," such as DNA methylation and histone modification -
Answers-alter DNA accessibility and chromatin structure, thereby regulating patterns of
gene expression.
.histone modifications - Answers-A histone modification is a covalent post-translational
modification (PTM) to histone proteins which includes methylation, phosphorylation,
acetylation, ubiquitylation, and sumoylation. The PTMs made to histones can impact
gene expression by altering chromatin structure or recruiting histone modifiers. Histone
proteins act to package DNA, which wraps around the eight histones, into
chromosomes. Histone modifications act in diverse biological processes such as
transcriptional activation/inactivation, chromosome packaging, and DNA damage/repair.
Quantitative detection of various histone modifications would provide useful information
for a better understanding of epigenetic regulation of cellular processes and the
development of histone modifying enzyme-targeted drugs.
.Prader-Willi syndrome - Answers-Prader-Willi syndrome is a complex genetic condition
that affects many parts of the body. In infancy, this condition is characterized by weak
muscle tone (hypotonia), feeding difficulties, poor growth, and delayed development.
Beginning in childhood, affected individuals develop an insatiable appetite, which leads
to chronic overeating (hyperphagia) and obesity. Some people with Prader-Willi
syndrome, particularly those with obesity, also develop type 2 diabetes (the most
common form of diabetes)
.Angelman syndrome - Answers-Angelman syndrome is a complex genetic disorder that
primarily affects the nervous system. Characteristic features of this condition include
delayed development, intellectual disability, severe speech impairment, and problems
with movement and balance (ataxia). Most affected children also have recurrent
seizures (epilepsy) and a small head size (microcephaly). Delayed development
becomes noticeable by the age of 6 to 12 months, and other common signs and
symptoms usually appear in early childhood.
.Prader-Willi Syndrome vs. Angelman syndrome - Answers-Prader-Willi syndrome
(PWS) and Angelman syndrome (AS) are clinically distinct complex disorders mapped
to chromosome 15q11-q13. They both have characteristic neurologic, developmental,
and behavioral phenotypes plus other structural and functional abnormalities. However,
the cognitive and neurologic impairment is more severe in AS, including seizures and
ataxia. The behavioral and endocrine disorders are more severe in PWS, including
, obsessive-compulsive symptoms and hypothalamic insufficiency. Both disorders can
result from microdeletion, uniparental disomy, or an imprinting center defect in 15q11-
q13, although the abnormality is on the paternally derived chromosome 15 for PWS and
the maternally derived 15 for AS because of genomic imprinting. Although the same
gene may control imprinting for both disorders, the gene(s) causing their phenotypes
differ. AS results from underexpression of a single gene, UBE3A, which codes for E6-
AP, a protein that functions to transfer small ubiquitin molecules to certain target
proteins, to enable their degradation. The genes responsible for PWS are not
determined, although several maternally imprinted genes in 15q11-q13 are known. The
most likely candidate is SNRPN, which codes for a small nuclear ribonucleoprotein, a
ribosome-associated protein that controls gene splicing and thus synthesis of critical
proteins in the brain. Animal models exist for both disorders. The genetic relationship
between PWS and AS makes them unique and potentially highly instructive disorders
that contribute substantially to the population burden of cognitive impairment.
.When do circulating erythrocytes play a major role in delivering oxygen to the tissues -
Answers-The after two weeks of gestation
.When does the production of erythrocytes shift from the vessels to deliver sinusoids? -
Answers-At approximately the eighth week of gestation the site shifts from the vessels
to deliver sinusoidal. The production of leukocytes and platelets begin in the liver and
spleen. Erythropoiesis in the liver and in the spleen and lymph nodes, reaches a peak at
approximately four months.
.Hematopoiesis begins to occur in the bone marrow in the fifth month increases rapidly
until red marrow fills _________________________ - Answers-Entire bone marrow
space.
.By the time of delivery, the _________________ is the only significant site of
hematopoiesis - Answers-Marrow
.hematopoetic marrow bills the bony cavities of the entire axial skeleton and many intra-
membranous bones in what age group? - Answers-Neonates and young infants
.Fatty (yellow) marrow gradually replaces hematopoetc _________________ -
Answers-Marrow
.Lymphocytes of children have more_____________ and less____________ than do
the lymphocytes of adult - Answers-Cytoplasm; compact nuclearchromatin
.Infectivity - Answers-Ability of the pathogen to establish an infection.
The pathogen capacity or horizontal transmission not in a parent-child relationship.
Well will
Answers
Epigenetics - Answers-heritable alterations that are not due to changes in DNA
sequence
.epigenetic modifications, or "tags," such as DNA methylation and histone modification -
Answers-alter DNA accessibility and chromatin structure, thereby regulating patterns of
gene expression.
.histone modifications - Answers-A histone modification is a covalent post-translational
modification (PTM) to histone proteins which includes methylation, phosphorylation,
acetylation, ubiquitylation, and sumoylation. The PTMs made to histones can impact
gene expression by altering chromatin structure or recruiting histone modifiers. Histone
proteins act to package DNA, which wraps around the eight histones, into
chromosomes. Histone modifications act in diverse biological processes such as
transcriptional activation/inactivation, chromosome packaging, and DNA damage/repair.
Quantitative detection of various histone modifications would provide useful information
for a better understanding of epigenetic regulation of cellular processes and the
development of histone modifying enzyme-targeted drugs.
.Prader-Willi syndrome - Answers-Prader-Willi syndrome is a complex genetic condition
that affects many parts of the body. In infancy, this condition is characterized by weak
muscle tone (hypotonia), feeding difficulties, poor growth, and delayed development.
Beginning in childhood, affected individuals develop an insatiable appetite, which leads
to chronic overeating (hyperphagia) and obesity. Some people with Prader-Willi
syndrome, particularly those with obesity, also develop type 2 diabetes (the most
common form of diabetes)
.Angelman syndrome - Answers-Angelman syndrome is a complex genetic disorder that
primarily affects the nervous system. Characteristic features of this condition include
delayed development, intellectual disability, severe speech impairment, and problems
with movement and balance (ataxia). Most affected children also have recurrent
seizures (epilepsy) and a small head size (microcephaly). Delayed development
becomes noticeable by the age of 6 to 12 months, and other common signs and
symptoms usually appear in early childhood.
.Prader-Willi Syndrome vs. Angelman syndrome - Answers-Prader-Willi syndrome
(PWS) and Angelman syndrome (AS) are clinically distinct complex disorders mapped
to chromosome 15q11-q13. They both have characteristic neurologic, developmental,
and behavioral phenotypes plus other structural and functional abnormalities. However,
the cognitive and neurologic impairment is more severe in AS, including seizures and
ataxia. The behavioral and endocrine disorders are more severe in PWS, including
, obsessive-compulsive symptoms and hypothalamic insufficiency. Both disorders can
result from microdeletion, uniparental disomy, or an imprinting center defect in 15q11-
q13, although the abnormality is on the paternally derived chromosome 15 for PWS and
the maternally derived 15 for AS because of genomic imprinting. Although the same
gene may control imprinting for both disorders, the gene(s) causing their phenotypes
differ. AS results from underexpression of a single gene, UBE3A, which codes for E6-
AP, a protein that functions to transfer small ubiquitin molecules to certain target
proteins, to enable their degradation. The genes responsible for PWS are not
determined, although several maternally imprinted genes in 15q11-q13 are known. The
most likely candidate is SNRPN, which codes for a small nuclear ribonucleoprotein, a
ribosome-associated protein that controls gene splicing and thus synthesis of critical
proteins in the brain. Animal models exist for both disorders. The genetic relationship
between PWS and AS makes them unique and potentially highly instructive disorders
that contribute substantially to the population burden of cognitive impairment.
.When do circulating erythrocytes play a major role in delivering oxygen to the tissues -
Answers-The after two weeks of gestation
.When does the production of erythrocytes shift from the vessels to deliver sinusoids? -
Answers-At approximately the eighth week of gestation the site shifts from the vessels
to deliver sinusoidal. The production of leukocytes and platelets begin in the liver and
spleen. Erythropoiesis in the liver and in the spleen and lymph nodes, reaches a peak at
approximately four months.
.Hematopoiesis begins to occur in the bone marrow in the fifth month increases rapidly
until red marrow fills _________________________ - Answers-Entire bone marrow
space.
.By the time of delivery, the _________________ is the only significant site of
hematopoiesis - Answers-Marrow
.hematopoetic marrow bills the bony cavities of the entire axial skeleton and many intra-
membranous bones in what age group? - Answers-Neonates and young infants
.Fatty (yellow) marrow gradually replaces hematopoetc _________________ -
Answers-Marrow
.Lymphocytes of children have more_____________ and less____________ than do
the lymphocytes of adult - Answers-Cytoplasm; compact nuclearchromatin
.Infectivity - Answers-Ability of the pathogen to establish an infection.
The pathogen capacity or horizontal transmission not in a parent-child relationship.
Well will
