https://wikimd.org/index.php?action=history&feed=atom&title=Zone_of_polarizing_activity 2026-04-26T18:14:21Z Revision history for this page on the wiki MediaWiki 1.44.2 https://wikimd.org/index.php?title=Zone_of_polarizing_activity&diff=6322622&oldid=prev 2025-02-18T11:21:23Z

<p>CSV import</p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 11:21, 18 February 2025</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l27">Line 27:</td> <td colspan="2" class="diff-lineno">Line 27:</td></tr> <tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Category:Embryology]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; 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white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">&lt;gallery&gt;</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">File:Limb_bud_diagram.jpg|Limb bud diagram</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">File:zpa1.jpg|Zone of polarizing activity</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">File:zpa2.jpg|Zone of polarizing activity</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">File:limbbud.jpg|Limb bud</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">File:Zone_polarisierender_Aktivität_in_der_Extrmeitätenknospe_(ZPA).jpg|Zone of polarizing activity in the limb bud</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">File:transfection.jpg|Transfection</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">File:limbbud3.jpg|Limb bud</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">File:bones23.jpg|Zone of polarizing activity</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">File:limbud5.jpg|Limb bud</ins></div></td></tr> <tr><td colspan="2" class="diff-side-deleted"></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">&lt;/gallery&gt;</ins></div></td></tr> </table>

Prab https://wikimd.org/index.php?title=Zone_of_polarizing_activity&diff=5334748&oldid=prev 2024-02-29T13:42:45Z

<p></p> <p><b>New page</b></p><div>== Zone of Polarizing Activity ==<br /> The &#039;&#039;&#039;Zone of Polarizing Activity&#039;&#039;&#039; (&#039;&#039;&#039;ZPA&#039;&#039;&#039;) is a region located at the posterior margin of the limb bud that plays a crucial role in the early development of limbs in vertebrates. It is responsible for the anterior-posterior organization (thumb to little finger axis) of the limb.<br /> <br /> == Function ==<br /> <br /> The ZPA functions by secreting a protein called [[Sonic hedgehog]] (Shh), which acts as a morphogen to control the growth and patterning of the limb. The concentration gradient of Shh across the limb bud determines the identity of the digits in a dose-dependent manner. High concentrations of Shh induce the formation of posterior digits, while lower concentrations are required for the formation of anterior digits.<br /> <br /> == Discovery ==<br /> <br /> The ZPA was first identified in the 1960s by [[John Saunders]] and his student [[John Fallon]]. They discovered that grafting an additional ZPA to the anterior margin of a chick limb bud resulted in a mirror-image duplication of the digits.<br /> <br /> == Role in Developmental Disorders ==<br /> <br /> Abnormalities in the ZPA or its signaling pathway can lead to limb malformations such as [[polydactyly]] (extra digits) and [[syndactyly]] (fused digits). Understanding the function of the ZPA and its signaling pathway can therefore provide insights into the causes of these developmental disorders.<br /> <br /> == See Also ==<br /> <br /> * [[Limb development]]<br /> * [[Morphogen]]<br /> * [[Sonic hedgehog]]<br /> <br /> == References ==<br /> <br /> &lt;references /&gt;<br /> <br /> [[Category:Developmental biology]]<br /> [[Category:Embryology]]<br /> [[Category:Vertebrate anatomy]]</div>

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