Developmental Biology Exam 3
Questions With Correct Answers
Organizer - CORRECT ANSWER✔✔-Forms on the dorsal side of the embryo. Its
| | | | | | | | | | | |
cells come to lie under the future Ectoderm. Capable of inducing cells around it to
| | | | | | | | | | | | | |
become neural Ectoderm; crucial to axis specification
| | | | | | |
Grey Crescent - CORRECT ANSWER✔✔-Visible in some frog species, it becomes
| | | | | | | | | | |
visible as a rotation of the outer surface of the zygote with respect to the deeper,
| | | | | | | | | | | | | | | |
subcortical cytoplasm; forms after fertilization due to reorganization of the one-
| | | | | | | | | |
cell zygote; crucial for formation of axial structures
| | | | | | |
Cortical Rotation - CORRECT ANSWER✔✔-Necessary for formation of axial
| | | | | | | | |
structures
Microtubules align during this time | | | | |
Can be induced to rescue UV treated embryos
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Animal Cap - CORRECT ANSWER✔✔-Cells from the roof of the blastocoel in the
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animal hemisphere
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Marginal Cells - CORRECT ANSWER✔✔-On their own would become ectoderm,
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however, when they receive signals from vegetal cells they become mesoderm
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cells
, Nieuwkoop Center - CORRECT ANSWER✔✔-Induces the organizer
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Signaling center in the future dorsal endoderm
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Dishevelled - CORRECT ANSWER✔✔-Displaced formally. Inactivates GSK3 by
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releasing it from the destruction complex and preventing it from binding beta
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catenin and targeting it for destruction
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XWnt11 mRNA - CORRECT ANSWER✔✔-If synthesis is suppressed the organizer
| | | | | | | | | |
fails to form. Localized to vegetal cortex during oogenesis and translocated to the
| | | | | | | | | | | | |
future dorsal portion of the embryo by the cortical rotation of the egg cytoplasm
| | | | | | | | | | | | |
Beta-Catenin - CORRECT ANSWER✔✔-synthesized throughout the embryo from
| | | | | | | |
maternal mRNA, accumulates in the dorsal region of the egg during cytoplasmic
| | | | | | | | | | | |
movements of fertilization and continues to accumulate preferentially at the
| | | | | | | | | |
dorsal side throughout early cleavage (nuclei of dorsal side)
| | | | | | | |
Siamois - CORRECT ANSWER✔✔-Gene that encodes homeodomain TF and
| | | | | | | | |
expressed in the organizer region immediately following the mid blastula
| | | | | | | | | |
transition. If ectopically expressed in ventral cells a second axis emerges on the
| | | | | | | | | | | | |
former ventral side of the embryo. If cortical microtubular polymerization is
| | | | | | | | | | |
prevented expression is limited | | |
Twin - CORRECT ANSWER✔✔-Gene that encodes homeodomain TF and
| | | | | | | | |
expressed in the organizer region immediately following the mid blastula
| | | | | | | | | |
transition. If ectopically expressed in ventral cells a second axis emerges on the
| | | | | | | | | | | | |
former ventral side of the embryo
| | | | |
Questions With Correct Answers
Organizer - CORRECT ANSWER✔✔-Forms on the dorsal side of the embryo. Its
| | | | | | | | | | | |
cells come to lie under the future Ectoderm. Capable of inducing cells around it to
| | | | | | | | | | | | | |
become neural Ectoderm; crucial to axis specification
| | | | | | |
Grey Crescent - CORRECT ANSWER✔✔-Visible in some frog species, it becomes
| | | | | | | | | | |
visible as a rotation of the outer surface of the zygote with respect to the deeper,
| | | | | | | | | | | | | | | |
subcortical cytoplasm; forms after fertilization due to reorganization of the one-
| | | | | | | | | |
cell zygote; crucial for formation of axial structures
| | | | | | |
Cortical Rotation - CORRECT ANSWER✔✔-Necessary for formation of axial
| | | | | | | | |
structures
Microtubules align during this time | | | | |
Can be induced to rescue UV treated embryos
| | | | | | |
Animal Cap - CORRECT ANSWER✔✔-Cells from the roof of the blastocoel in the
| | | | | | | | | | | | |
animal hemisphere
|
Marginal Cells - CORRECT ANSWER✔✔-On their own would become ectoderm,
| | | | | | | | | |
however, when they receive signals from vegetal cells they become mesoderm
| | | | | | | | | | |
cells
, Nieuwkoop Center - CORRECT ANSWER✔✔-Induces the organizer
| | | | | |
Signaling center in the future dorsal endoderm
| | | | | |
Dishevelled - CORRECT ANSWER✔✔-Displaced formally. Inactivates GSK3 by
| | | | | | | |
releasing it from the destruction complex and preventing it from binding beta
| | | | | | | | | | | |
catenin and targeting it for destruction
| | | | |
XWnt11 mRNA - CORRECT ANSWER✔✔-If synthesis is suppressed the organizer
| | | | | | | | | |
fails to form. Localized to vegetal cortex during oogenesis and translocated to the
| | | | | | | | | | | | |
future dorsal portion of the embryo by the cortical rotation of the egg cytoplasm
| | | | | | | | | | | | |
Beta-Catenin - CORRECT ANSWER✔✔-synthesized throughout the embryo from
| | | | | | | |
maternal mRNA, accumulates in the dorsal region of the egg during cytoplasmic
| | | | | | | | | | | |
movements of fertilization and continues to accumulate preferentially at the
| | | | | | | | | |
dorsal side throughout early cleavage (nuclei of dorsal side)
| | | | | | | |
Siamois - CORRECT ANSWER✔✔-Gene that encodes homeodomain TF and
| | | | | | | | |
expressed in the organizer region immediately following the mid blastula
| | | | | | | | | |
transition. If ectopically expressed in ventral cells a second axis emerges on the
| | | | | | | | | | | | |
former ventral side of the embryo. If cortical microtubular polymerization is
| | | | | | | | | | |
prevented expression is limited | | |
Twin - CORRECT ANSWER✔✔-Gene that encodes homeodomain TF and
| | | | | | | | |
expressed in the organizer region immediately following the mid blastula
| | | | | | | | | |
transition. If ectopically expressed in ventral cells a second axis emerges on the
| | | | | | | | | | | | |
former ventral side of the embryo
| | | | |
