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What
are the known characteristics of the ZPA?
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1. |
If
ZPA is transplanted (at the correct time) to an
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ectopic
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site
it will respecify tissue.
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2. It
acts to induce the correct A/P pattern via
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a
concentration gradient.
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3.
Acts over a very narrow time frame.
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4.
The activity of the ZPA is universal among
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quadrapeds and is the same for the fore
limb and hind
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limb.
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