T. Thomson Flynn and the monotreme egg from oocyte maturation to germ layer formation,Journal of Morphology

当前位置： X-MOL 学术 › J. Morphol. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

T. Thomson Flynn and the monotreme egg from oocyte maturation to germ layer formation
Journal of Morphology ( IF 1.5 ) Pub Date : 2021-01-13 , DOI: 10.1002/jmor.21319
Anthony M Carter ₁

Affiliation

Knowledge of oocyte development and the early differentiation of the germ layers in monotremes stems largely from two papers by J. P. Hill and T. Thomson Flynn. The completeness of their account was due to the large series of echidna ovaries and eggs collected on Tasmania by Flynn, an Australian biologist of whom a brief account is given. A striking finding in the oocyte and early embryo of monotremes was the presence of a latebra connected to the yolk bed beneath the germinal disc as described in birds and several reptiles. A further resemblance was the presence early in vitellogenesis of a striate zone beneath the zona pellucida. Cleavage resulted first in a lens-shaped blastodisc encircled by cells called vitellocytes that later fused to form a germ-ring. The blastodisc gave rise to a blastoderm that eventually became unilaminar but comprised two cell types identified as ectoderm and primitive endoderm. Eventually these segregated into two layers and formed a blastula. This sequence resembled that in marsupials except there was no obvious distinction between future embryonic and extra-embryonic regions. As the blastoderm extended over the surface of the yolk, it was preceded by the germ-ring that eventually played a role in forming the yolk navel. This was a unique feature of monotreme development. It is shown that Flynn played an important role in analysis of the material as well as in its collection.

中文翻译：

T. Thomson Flynn 和单孔目卵子从卵母细胞成熟到胚层形成

卵母细胞发育和单孔目动物胚层早期分化的知识主要来自 JP Hill 和 T. Thomson Flynn 的两篇论文。他们的描述之所以完整，是因为弗林在塔斯马尼亚收集了大量针鼹卵巢和卵，弗林是澳大利亚生物学家，对此进行了简要说明。在单孔目动物的卵母细胞和早期胚胎中的一个惊人发现是，如鸟类和几种爬行动物所描述的那样，存在与生发盘下方的卵黄床相连的晚乳头。另一个相似之处是在透明带下方的条纹区域的卵黄形成早期存在。卵裂首先产生透镜状胚盘，周围被称为卵黄细胞的细胞包围，随后融合形成胚环。胚盘产生了最终成为单层的胚盘，但包含两种细胞类型，分别为外胚层和原始内胚层。最终这些分离成两层并形成囊胚。这个序列类似于有袋动物，只是未来胚胎和胚胎外区域之间没有明显区别。当胚盘延伸到蛋黄表面时，它之前是胚芽环，最终在形成蛋黄肚中发挥了作用。这是单孔目开发的一个独特特征。事实证明，弗林在材料分析及其收藏中发挥了重要作用。这个序列类似于有袋动物，只是未来胚胎和胚胎外区域之间没有明显区别。当胚盘延伸到蛋黄表面时，它之前是胚芽环，最终在形成蛋黄肚中发挥了作用。这是单孔目开发的一个独特特征。事实证明，弗林在材料分析及其收藏中发挥了重要作用。这个序列类似于有袋动物，只是未来胚胎和胚胎外区域之间没有明显区别。当胚盘延伸到蛋黄表面时，它之前是胚芽环，最终在形成蛋黄肚中发挥了作用。这是单孔目开发的一个独特特征。事实证明，弗林在材料分析及其收藏中发挥了重要作用。

更新日期：2021-01-13

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11