Role of AER and PZ
in determining
proximal-distal limb polarity
Removal
of the AER at various stages of
limb development interrupts limb formation
at various stages.
If AER is removed
early - only a
humerus (most
proximal part) forms
If AER is removed
later - humerus, ulna
and radius form.
Experiment 1:
Experiment 2:
A) When wing-bud
PZ
from
young
embryo
was
transplanted onto a old
embryo’s
wing bud (one that had
humerus, ulna and radius already
formed)
extra set of early and
intermediate structures
(humerus,
ulna and radius)
is formed
B) When
old embryo’s
wing-bud
PZ
was
transplanted onto young
embryo’s
wing bud
intermediate
structures do not form
Role of AER and PZ
in determining
proximal-distal limb polarity
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- Summer '14
- Sonic hedgehog, limb development
