BIO 351 FINAL EXAM 2025
QUESTIONS AND ANSWERS 100%
PASS
Which of the following adult structures is derived from somites? - ✔✔tendons,
vertebrae
Cells that become the _________ undergo a ____________ to __________ transition first.
Fill in the blanks. - ✔✔Sclerotome, epithelial, mesenchymal
The endocardial cushion cells have important roles in heart formation. Defects in the
endocardial cushions have been associated with which of the following? - ✔✔septation
defects
Spondylocostal dysostosis and congenital scoliosis are examples of disruption of which
of the following genetic pathways? - ✔✔Notch
Somitogenesis is a developmental process that involves multiple steps regulated by
specific gene interactions. Which of the following correctly matches the gene/factor and
its action during somitogenesis? - ✔✔FGF8/Wnt3a and retinoic acid, location of the
determination front
Which of the following tissues is derived from the paraxial mesoderm? -
✔✔dermomyotome, syndetome, sclerotome
Which of the following is the correct order of the neural tube defects from least to most
severe? - ✔✔spina bifida occulta, myelomeningocele, anecephaly
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,Situs inversus is a rare genetic condition where the normally asymmetric localization of
internal organs is inverted. A mutation in which of the following genes is most likely
linked to this condition? - ✔✔Dnah11 - a cytoskeletal component that regulates cilia
motility
The long axis of the neural tube runs along which axis? - ✔✔rostral-caudal
The neural tube is derived which of the following germ layers? - ✔✔ectoderm
Dorsal-ventral specification of the neural tube is regulated by secretion of which of the
following? - ✔✔BMP4/7 from the roof plate (dorsal) / Shh from the notochord (ventral)
The developing human gastrula is patterned along the anterior-posterior axis by a
number of secreted cues. The anterior visceral endoderm migrates from the _________
tip and secretes Wnt antagonists that direct appropriate patterning along the
___________ axis. - ✔✔distal, anterior-posterior
Which of the following structures is NOT derived from the epiblast in a human
embryo?
a. trophoblast
b. mesoderm
c. ectoderm
d. endoderm - ✔✔trophoblast
Melanocytes are derived from which embryonic tissue? - ✔✔neural crest
Which cytoskeletal component is particularly enriched in the shaft of a growing axon? -
✔✔microtubules
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,Neural crest is formed when cells from the ___________ region of the neural tube
change shape from ___________ to ____________ morphology. - ✔✔dorsal, epithelial,
mesenchymal
Which of the following disorders would results from embryonic exposure to
cyclopamine, an inhibitor of SHH signaling? - ✔✔cyclopia
The segmental organization of peripheral nerves in the spinal cord depends heavily
upon _______. - ✔✔Ephrin mediated repulsion of neural crest and axons from the
caudal somite
A lack of Schwann cells and the absence of major nerve clusters, such as the
sympathetic ganglia, most likely resulted from defects in which of the following cell
types? - ✔✔neural crest
Which cytoskeletal component is found at particularly high concentrations underneath
the plasma membrane of an active growth cone. - ✔✔actin
Nociceptive neurons mediate ____ and are dependent upon _____ during development.
- ✔✔pain, NGF
Tbx5 is expressed in the developing limbs and heart. You want to examine the role of
Tbx5 in the development of the limb only. Which approach would you choose? -
✔✔Cre/Lox using a limb specific promoter driving Cre expression and a floxed Tbx5
gene
Skeletal muscles that form the deep muscles of the back derive from ____________. -
✔✔dorsal medial lip (DML)
Boniva (ibandronic acid) is a commonly marketed drug for osteoporosis to increase
bone mass. It acts by inhibiting the action of which of the following cells? -
✔✔osteoclasts
COPYRIGHT © 2025 BY SOPHIA BENNETT, ALL RIGHTS RESERVED 3
, Osteogenesis imperfecta is a disease that results from a genetic mutation that disrupts
the formation of ____________ that is required for strength of bone. - ✔✔collagen I
In the embryo, the early skeletal muscle originates from the __________. In the adult,
skeletal muscle is repaired by fusion of ____________ with muscle fibers. Fill in the
blanks. - ✔✔myotome, satellite cells
Which of the following correctly matches a cell type in bone and its function? -
✔✔osteoclast, bone resorption
Skeletal muscles of the jaw derive from ___________ while deep muscles of the back
derive from ____________. - ✔✔Neural crest, DML of the dermamyotome
Which of the following cell types is formed from epiblast cells that migrate through the
primitive streak? - ✔✔.mesoderm - the mesoderm forms from the epiblast cells
migrating through the primitive streak.
All the cells of the embryo proper (all the cells in your body now) derive from which of
the following cells? - ✔✔epiblast
In the mammalian embryo, which structure is essential to set up the anterior-posterior
axis? - ✔✔Anterior visceral endoderm
A 25 year-old woman who is pregnant for the first time undergoes amniocentesis
during the 25th week of pregnancy. This testing reveals an increased level of
acetylcholinesterase in the amniotic fluid. Acetylcholinesterase is normally produced in
the CNS and cannot cross the blood brain barrier. This test suggests which of the
following fetal abnormalities? - ✔✔Anencephaly-CORRECT, the neural tube is open in
the head and exposed to amniotic fluid
The neural tube is regionalized by developmental gene regulation. Which of the
following correctly matches the gene and specified region? - ✔✔Shh - ventralizing the
neural tube-CORRECT, Shh is release by the notochord and ventralizes the neural tube
COPYRIGHT © 2025 BY SOPHIA BENNETT, ALL RIGHTS RESERVED 4
QUESTIONS AND ANSWERS 100%
PASS
Which of the following adult structures is derived from somites? - ✔✔tendons,
vertebrae
Cells that become the _________ undergo a ____________ to __________ transition first.
Fill in the blanks. - ✔✔Sclerotome, epithelial, mesenchymal
The endocardial cushion cells have important roles in heart formation. Defects in the
endocardial cushions have been associated with which of the following? - ✔✔septation
defects
Spondylocostal dysostosis and congenital scoliosis are examples of disruption of which
of the following genetic pathways? - ✔✔Notch
Somitogenesis is a developmental process that involves multiple steps regulated by
specific gene interactions. Which of the following correctly matches the gene/factor and
its action during somitogenesis? - ✔✔FGF8/Wnt3a and retinoic acid, location of the
determination front
Which of the following tissues is derived from the paraxial mesoderm? -
✔✔dermomyotome, syndetome, sclerotome
Which of the following is the correct order of the neural tube defects from least to most
severe? - ✔✔spina bifida occulta, myelomeningocele, anecephaly
COPYRIGHT © 2025 BY SOPHIA BENNETT, ALL RIGHTS RESERVED 1
,Situs inversus is a rare genetic condition where the normally asymmetric localization of
internal organs is inverted. A mutation in which of the following genes is most likely
linked to this condition? - ✔✔Dnah11 - a cytoskeletal component that regulates cilia
motility
The long axis of the neural tube runs along which axis? - ✔✔rostral-caudal
The neural tube is derived which of the following germ layers? - ✔✔ectoderm
Dorsal-ventral specification of the neural tube is regulated by secretion of which of the
following? - ✔✔BMP4/7 from the roof plate (dorsal) / Shh from the notochord (ventral)
The developing human gastrula is patterned along the anterior-posterior axis by a
number of secreted cues. The anterior visceral endoderm migrates from the _________
tip and secretes Wnt antagonists that direct appropriate patterning along the
___________ axis. - ✔✔distal, anterior-posterior
Which of the following structures is NOT derived from the epiblast in a human
embryo?
a. trophoblast
b. mesoderm
c. ectoderm
d. endoderm - ✔✔trophoblast
Melanocytes are derived from which embryonic tissue? - ✔✔neural crest
Which cytoskeletal component is particularly enriched in the shaft of a growing axon? -
✔✔microtubules
COPYRIGHT © 2025 BY SOPHIA BENNETT, ALL RIGHTS RESERVED 2
,Neural crest is formed when cells from the ___________ region of the neural tube
change shape from ___________ to ____________ morphology. - ✔✔dorsal, epithelial,
mesenchymal
Which of the following disorders would results from embryonic exposure to
cyclopamine, an inhibitor of SHH signaling? - ✔✔cyclopia
The segmental organization of peripheral nerves in the spinal cord depends heavily
upon _______. - ✔✔Ephrin mediated repulsion of neural crest and axons from the
caudal somite
A lack of Schwann cells and the absence of major nerve clusters, such as the
sympathetic ganglia, most likely resulted from defects in which of the following cell
types? - ✔✔neural crest
Which cytoskeletal component is found at particularly high concentrations underneath
the plasma membrane of an active growth cone. - ✔✔actin
Nociceptive neurons mediate ____ and are dependent upon _____ during development.
- ✔✔pain, NGF
Tbx5 is expressed in the developing limbs and heart. You want to examine the role of
Tbx5 in the development of the limb only. Which approach would you choose? -
✔✔Cre/Lox using a limb specific promoter driving Cre expression and a floxed Tbx5
gene
Skeletal muscles that form the deep muscles of the back derive from ____________. -
✔✔dorsal medial lip (DML)
Boniva (ibandronic acid) is a commonly marketed drug for osteoporosis to increase
bone mass. It acts by inhibiting the action of which of the following cells? -
✔✔osteoclasts
COPYRIGHT © 2025 BY SOPHIA BENNETT, ALL RIGHTS RESERVED 3
, Osteogenesis imperfecta is a disease that results from a genetic mutation that disrupts
the formation of ____________ that is required for strength of bone. - ✔✔collagen I
In the embryo, the early skeletal muscle originates from the __________. In the adult,
skeletal muscle is repaired by fusion of ____________ with muscle fibers. Fill in the
blanks. - ✔✔myotome, satellite cells
Which of the following correctly matches a cell type in bone and its function? -
✔✔osteoclast, bone resorption
Skeletal muscles of the jaw derive from ___________ while deep muscles of the back
derive from ____________. - ✔✔Neural crest, DML of the dermamyotome
Which of the following cell types is formed from epiblast cells that migrate through the
primitive streak? - ✔✔.mesoderm - the mesoderm forms from the epiblast cells
migrating through the primitive streak.
All the cells of the embryo proper (all the cells in your body now) derive from which of
the following cells? - ✔✔epiblast
In the mammalian embryo, which structure is essential to set up the anterior-posterior
axis? - ✔✔Anterior visceral endoderm
A 25 year-old woman who is pregnant for the first time undergoes amniocentesis
during the 25th week of pregnancy. This testing reveals an increased level of
acetylcholinesterase in the amniotic fluid. Acetylcholinesterase is normally produced in
the CNS and cannot cross the blood brain barrier. This test suggests which of the
following fetal abnormalities? - ✔✔Anencephaly-CORRECT, the neural tube is open in
the head and exposed to amniotic fluid
The neural tube is regionalized by developmental gene regulation. Which of the
following correctly matches the gene and specified region? - ✔✔Shh - ventralizing the
neural tube-CORRECT, Shh is release by the notochord and ventralizes the neural tube
COPYRIGHT © 2025 BY SOPHIA BENNETT, ALL RIGHTS RESERVED 4
