EEB 184 - EXAM 2 QUESTIONS WITH CORRECT
ANSWERS.2025/2026
Proximal to distal - ----Answers---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 - ----Answers---The forelimb has three limb segments, the stylopod, zeugopod, and autopod. Which bone(s) are in the zeugopod?
Humerus - ----Answers---The forelimb has three limb segments, the stylopod, zeugopod, and autopod. Which bone(s) are in the stylopod?
Carpals and digits - ----Answers---The forelimb has three limb segments, the stylopod, zeugopod, and autopod. Which bone(s) are in the autopod?
Hox genes - ----Answers---Which gene family helps control cell fates along the proximal-distal axis of the developing limb?
cell proliferation - ----Answers---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) - ----Answers---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? 1 / 2
progress zone - ----Answers---The massive progenitor cells building underneath the AER is called the...
Zone of Polarizing Activity (ZPA) - ----Answers---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 - ----Answers---If the AER is removed from the developing limb bud, what happens?
positive - ----Answers---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
- ----Answers---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 - --- -Answers---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 - --- -Answers---What would you expect to happen if the AER was removed later in limb development after outgrowth had begun?
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