EEB 184 - Exam 2 Latest
Update
Proximal to distal - Answer The limb has three axes. What is the name of the axis that
goes from the shoulder to the ends of the fingers?
Ulna and radius - Answer The forelimb has three limb segments, the stylopod,
zeugopod, and autopod. Which bone(s) are in the zeugopod?
Humerus - Answer The forelimb has three limb segments, the stylopod, zeugopod, and
autopod. Which bone(s) are in the stylopod?
Carpals and digits - Answer The forelimb has three limb segments, the stylopod,
zeugopod, and autopod. Which bone(s) are in the autopod?
Hox genes - Answer Which gene family helps control cell fates along the proximal-distal
axis of the developing limb?
cell proliferation - Answer Which of the following is a cellular process that needs to
happen for the limb to bring growing out from the body?
Apical Ectodermal Ridge (AER) - Answer What is the name of the structurally distinct
ridge of epithelium in the developing limb bud that is located at the most distal extent of
the limb bud and perfectly bisects the dorsal and ventral halve of the bud?
progress zone - Answer The massive progenitor cells building underneath the AER is
called the...
Zone of Polarizing Activity (ZPA) - Answer What is the name of the distinct region of the
limb bud that is restricted to a small portion of the posterior most bud and that, when
transplanted, can cause the mirror image duplication of digits?
limb development ceases - Answer If the AER is removed from the developing limb bud,
what happens?
positive - Answer The AER, ZPA, and Progress Zone interact to pattern and control limb
development. What is the nature of the interactions between these elements?
Limb would grow out but the limb axes (e.g.,DV) would be disrupted - Answer How
would you expect forelimb outgrowth to be impacted by the shift in Hox Gene expression
shown (in image 1A)
Autopod and zeugopod would not form, but stylopod would form - Answer What would
, you expect to happen if the AER was
removed early before outgrowth began?
Autopod and zeugopod would not form, but stylopod would form - Answer What would
you expect to happen if the AER was
removed later in limb development after outgrowth had begun?
AER - Answer _______ drives cell proliferation and regulates limb outgrowth
ZPA - Answer _______ patterns the AP axis, also contributes to cell proliferation
Limb structures would be repeated in a
mirror-like pattern - Answer Assume you added a second ZPA to the anterior side of the
limb (see image 1B). What phenotype would you
expect to observe in the resulting chick limb?
Resulting embryos would die before limb development occurred - Answer In the mouse
(on image 1C), Shh was only knocked out during limb development using a special
technique. What would happen if a mutation was instead introduced into the
protein-coding region of Shh?
Shh - Answer The earlier______ was removed, the fewer digits were formed
webbing - Answer Bmps that don't die create...
Negative - Answer Retinoic acid and Fibroblast growth factors (FGF) interact. What is
the nature of this interaction?
Tbx5 is expressed in the forelimb, Tbx4 is expressed in the hind limb - Answer TBX
genes have been found to be expressed early in the outgrowth of the fore- and hind limb.
Which gene(s) have been found to be expressed in which limb?
Fgf8 - Answer What is a primary gene produced by the AER that signals to the progress
zone?
Wnt - Bmp - Answer Which of the following morphogenetic gradients is important in
setting up the dorsal to ventral axis of the developing limb?
RA - Fgf8 - Answer Which of the following morphogenetic gradients is important in
setting up the proximal to distal axis of the developing limb?
Shh - Answer Which of the following morphogenetic gradients is important in setting up
the anterior to posterior axis of the developing limb?
stylopod - Answer The limb has three segments, the stylopod, zeugopod, and autopod.
Which segment emerges from a field with strong retinoic acid signaling and no fgf
signaling?
Update
Proximal to distal - Answer The limb has three axes. What is the name of the axis that
goes from the shoulder to the ends of the fingers?
Ulna and radius - Answer The forelimb has three limb segments, the stylopod,
zeugopod, and autopod. Which bone(s) are in the zeugopod?
Humerus - Answer The forelimb has three limb segments, the stylopod, zeugopod, and
autopod. Which bone(s) are in the stylopod?
Carpals and digits - Answer The forelimb has three limb segments, the stylopod,
zeugopod, and autopod. Which bone(s) are in the autopod?
Hox genes - Answer Which gene family helps control cell fates along the proximal-distal
axis of the developing limb?
cell proliferation - Answer Which of the following is a cellular process that needs to
happen for the limb to bring growing out from the body?
Apical Ectodermal Ridge (AER) - Answer What is the name of the structurally distinct
ridge of epithelium in the developing limb bud that is located at the most distal extent of
the limb bud and perfectly bisects the dorsal and ventral halve of the bud?
progress zone - Answer The massive progenitor cells building underneath the AER is
called the...
Zone of Polarizing Activity (ZPA) - Answer What is the name of the distinct region of the
limb bud that is restricted to a small portion of the posterior most bud and that, when
transplanted, can cause the mirror image duplication of digits?
limb development ceases - Answer If the AER is removed from the developing limb bud,
what happens?
positive - Answer The AER, ZPA, and Progress Zone interact to pattern and control limb
development. What is the nature of the interactions between these elements?
Limb would grow out but the limb axes (e.g.,DV) would be disrupted - Answer How
would you expect forelimb outgrowth to be impacted by the shift in Hox Gene expression
shown (in image 1A)
Autopod and zeugopod would not form, but stylopod would form - Answer What would
, you expect to happen if the AER was
removed early before outgrowth began?
Autopod and zeugopod would not form, but stylopod would form - Answer What would
you expect to happen if the AER was
removed later in limb development after outgrowth had begun?
AER - Answer _______ drives cell proliferation and regulates limb outgrowth
ZPA - Answer _______ patterns the AP axis, also contributes to cell proliferation
Limb structures would be repeated in a
mirror-like pattern - Answer Assume you added a second ZPA to the anterior side of the
limb (see image 1B). What phenotype would you
expect to observe in the resulting chick limb?
Resulting embryos would die before limb development occurred - Answer In the mouse
(on image 1C), Shh was only knocked out during limb development using a special
technique. What would happen if a mutation was instead introduced into the
protein-coding region of Shh?
Shh - Answer The earlier______ was removed, the fewer digits were formed
webbing - Answer Bmps that don't die create...
Negative - Answer Retinoic acid and Fibroblast growth factors (FGF) interact. What is
the nature of this interaction?
Tbx5 is expressed in the forelimb, Tbx4 is expressed in the hind limb - Answer TBX
genes have been found to be expressed early in the outgrowth of the fore- and hind limb.
Which gene(s) have been found to be expressed in which limb?
Fgf8 - Answer What is a primary gene produced by the AER that signals to the progress
zone?
Wnt - Bmp - Answer Which of the following morphogenetic gradients is important in
setting up the dorsal to ventral axis of the developing limb?
RA - Fgf8 - Answer Which of the following morphogenetic gradients is important in
setting up the proximal to distal axis of the developing limb?
Shh - Answer Which of the following morphogenetic gradients is important in setting up
the anterior to posterior axis of the developing limb?
stylopod - Answer The limb has three segments, the stylopod, zeugopod, and autopod.
Which segment emerges from a field with strong retinoic acid signaling and no fgf
signaling?
