Principles of Development: Body, Limb, and Brain Patterning & Disorders Flashcards
A cell that can give rise to a number of different cell types of the same germ layer, but not that of a different germ layer is:
A. multipotent
B. pluripotent
C. terminally differentiated
D. totipotent
E. unipotent
A. multipotent
A cell that is capable of giving rise to all cells of an embryo except the extraembryonic membrane is described as:
A. multipotent
B. pluripotent
C. terminally differentiated
D. totipotent
E. unipotent
B. pluripotent
Patients with situs ambiguous are examples of errors in which of the following developmental processes?
A. Anterior-posterior (rostral-caudal) axis determination
B. Dorsoventrical axis determination
C. Left-right axis determination
D. Organogenesis
E. Segmentation
C. Left-right axis determination
Which of the following statements about the HOX genes is incorrect?
A. The code for cell surface receptors necessary for normal development
B. They demonstrate spatial colinearity with the developing embryo
C. They demonstrate temporal colinearity with the developing embryo
D. They play a role in determining the fate of cells in a developing embryo
E. They play a role in the positional identity of cell sin a developing embryo
A. The code for cell surface receptors necessary for normal development
A patient is found to have asplenia and two tri-lobed lungs. Which one of hte following diagnoses is most appropriate?
A. Absent spleen syndrome
B. Left isomerism
C. Right isomerism
D. Sinus inversus totalis
E. Sinus solitus
C. Right isomerism
- Spleen is on the left side of your body, so if missing you have right isomerism
- right lung is normally trilobed, so if both trilobed must be right isomerism
Which oen of the following body patterning follows the so called “Hox code”?
A. Dorsal-ventral patterning of the CNS
B. Dorsal-ventral patterning of the limbs
C. Left-right patterning
D. Proximal-distal patterning of the lib
E. Segmentation along the AP axis
E. Segmentation along the AP axis
The Hox code is important in specifying the locations of limb bud development relative to the location on the AP axis on either side of the early embryo.
In humans, the anterior digit is the thumb, and the posterior digit is the fifth finger.
Segmentation is determined by…
A. cadherin-mediated cell movement
B. cilia-mediated direction of fluid flow
C. DNA methylation and histone diacetylation
D. differential ratios of morphogen-gradient-mediated transcriptional regulation
E. Ubiquitin-mediated processes
D. differential ratios of morphogen-gradient-mediated transcriptional regulation
Which one of the following imparts posterior identity in limb development?
A. Apical ectodermal ridge
B. Notocord
C. Primitive streak
D. Progress zone
E. Zone of polarizing activity
E. Zone of polarizing activity
In the developing limb, a region of the posterior mesoderm, called the zone of polarizing activity
(ZPA), secretes Shh, which maintains the proximal to distal growth of the limb that is taking place at a distal region
of the limb ectoderm called the apical ectodermal ridge.
In humans, the anterior digit is the thumb, and the posterior digit is the fifth finger. Anterior-posterior patterning is controlled by a region in the posterior
margin of the limb called the zone of polarizing activity (ZPA). The ZPA confers posterior identity of limb mesenchymal cells. Grafting of ZPA to the anterior region of the limb bud results in mirror hand deformity. This
phenomenon suggests the action of a morphogen gradient in specifying digit identity. The critical morphogen in this case is sonic hedgehog (Shh).
Which class of the following signaling molecules is responsible for dorsal patterning in neural tube development?
A. Bone morphogenic protein
B. Cholesterol
C. Fibroblast growth factor
D. Goosecoid
E. Sonic hedgehog
A. Bone morphogenic protein
In order to maintain cell proliferation in the developing limb bud, the apical epidermal region secretes into the progress zone
A. FGF8
B. FGF10
C. Lefty
D. Lmx
E. Wnt-7a
A. FGF8
Sonic hedgehog plays a role in all of the following developmental processes except
A. determination of differentiation vs self-renewal in stem cells
B. determination of posterior identity of the distal limb
C. left-right axis determination
D. ventral patterning of the neural tube
A. determination of differentiation vs self-renewal in stem cells
The Nail-Patella syndrome is caused by defects in the LMX1B gene. This represents a defect in which one of the following?
A. Apoptosis
B. Dorsal patterning of the hand
C. Epidermal-mesenchymal interaction
D. Proximal-distal differentiation
E. Ventral patterning of the hand
B. Dorsal patterning of the hand
Mutations in the LMX1B gene cause the nail-patella syndrome, which is characterized by nail dysplasia,
absent or hypoplastic patella, and nephropathy. Since nail and patella are dorsal structures of the limb, this genetic defect can be understood from the developmental genetics standpoint, though much of the details still
require further investigation.
Rapid removal of key intracellular proteins is mediated by
A. Cadherin-mediated cell movement
B. Cilia-mediated direction of fluid flow
C. DNA methylation and histone deacetylation
D. Morphogen-gradient-mediated transcriptional regulation
E. Ubiquitin-mediated processes
E. Ubiquitin-mediated processes
Transcription silencing can be mediatd by
A. Cadherin-mediated cell movement
B. Cilia-mediated direction of fluid flow
C. DNA methylation and histone deacetylation
D. Morphogen-gradient-mediated transcriptional regulation
E. Ubiquitin-mediated processes
C. DNA methylation and histone deacetylation
Which one of the following signaling molecules is responsible for ventral patterning in neural development?
A. Bone morphogenic proteins
B. Brain-derived neuromorphic factor
C. Fibroblast growth factors
D. Nerve growth factor
E. Sonic hedgehog
E. Sonic hedgehog
Which one of the following steps is not necessary for the activation of the sonic hedgehog protein?
A. Attachment of cholesterol
B. Autolytic cleavage
C. Binding to glycosaminoglycan
D. Palmitoylation
E. Removal of signal sequence
C. Binding to glycosaminoglycan
A newborn infant is found to have dextrocardia (cardiac apex pointing to the right), bilobed right lung and trilobed left lung, polysplenia, and small bowel that loops clockwise. This arrangement of internal organs is best classified as
A. lex situs
B. situs ambiguous
C. situs incognitus
D. situs inversus
E. situs solitus
B. situs ambiguous
I guess this is because it doesn’t fit any of those options?
Asymmetric distribution of FGF8 during left-right axis determination
A. Cadherin-mediated cell movement
B. Cilia-mediated direction of fluid flow
C. DNA methylation and histone deacetylation
D. Morphogen-gradient-mediated transcriptional regulation
E. Ubiquitin-mediated processes
B. Cilia-mediated direction of fluid flow
FGF10 and FGF8 seem to have lots of overlap
Which of the following is not considered a midline defect commonly seen in assocaition with holoprosencephaly?
A. Cleft lip and/or palate
B. Hypertrophic pyloric stenosis
C. Hypopituitarism
D. Hypospadias
E. Single upper central incisor
B. Hypertrophic pyloric stenosis
can be associated with Shh gene
A 6 month old infant is found to have a short neck with poor rotational mobility. There is no other unusual physical finding. This abnormality is likely to represent a
A. AP axis error
B. DV axis error
Heterotaxy
D. Proximal-distal gradient error
E. Segmentation abnormality
E. Segmentation abnormality
Newborn examination of an infant reveal the PMI of the heart to be on the right chest, and chest X-ray further revealed dextrocardia as well as dextroversion of the heart. However, the chest x-ray also showed the stomach bubble to be onthe left, and the liver appears to be on the right side. On further investigation the left lung is tri-lobed and the right luht lung is bi-lobed, and the spleen is on the left side. This represents
A. Left isomerism
B. Right isomerism
C. situs invertus abdominalis
D. Situs invertus thoracalis
E. Situs inversus totalis
D. Situs invertus thoracalis
above the diaphragm it switches
left lung should be 2 lobes
right lung should be 3 lobes
Inborn errors of development are enzymatic deficiences that result in congenital malformation(s). All of the following is an example of that EXCEPT
A. 7-Dehydrocholesterol reductase deficiency
B. Galactose-1-phosphate uridyl transferase
C. Phosphomannomutase 2 deficiency
D. Pyruvate dehydrogenase deficiency
E. Tyrosine-protein phosphatase non-receptor type II (PTPN11) deficiency
B. Galactose-1-phosphate uridyl transferase
Wardenburg syndrome is characterized by craniofacial characteristics, hearing loss, patchy pigmentary allocations of hair and iris and absence of mysenteric ganglions in the colon. Which one of the following is the likely pathogenesis of this syndrome
A. Anterior-posterior segmentation
B/ Left-right determination
C. Melanogenesis
D. Neural crest migration
E. Neural tube formation
D. Neural crest migration
Deficiency of members of this group mostly results in eye devlopment.
A. FGF receptor genes
B. HOX genes
C. MYC genes
D. PAX genes
E. SHH signaling pathway genes
D. PAX genes
