allantoid

简明释义

英[əˈlæntɔɪd]美[əˈlænˌtɔɪd]

adj. 尿囊的，尿囊样的（等于 allantoidal）

n. 尿囊（等于 allantois）

英英释义

单词用法

同义词

反义词

例句

1.Main Ingredient: Sunflowers Seed Oil, Extracted Malvaceous Flower, Allantoid, VitaminB5, Wheat Plantule Pil, VitaminC, Whitening Gene, and Sheep-fuels Element.

主要成份：葵花籽油、锦葵精华、尿囊素、维生素B5、小麦胚芽油、维生素C、美白因子、羊胎素等。

2.Main Ingredient: Sunflowers Seed Oil, Extracted Malvaceous Flower, Allantoid, VitaminB5, Wheat Plantule Pil, VitaminC, Whitening Gene, and Sheep-fuels Element.

主要成份：葵花籽油、锦葵精华、尿囊素、维生素B5、小麦胚芽油、维生素C、美白因子、羊胎素等。

3.In reptiles, the allantoid serves as a respiratory organ.

在爬行动物中，尿囊作为呼吸器官。

4.The function of the allantoid in mammals is often overlooked.

哺乳动物中尿囊的功能常常被忽视。

5.During development, the allantoid helps in nutrient absorption.

在发育过程中，尿囊有助于营养物质的吸收。

6.The allantoid structure is crucial for waste storage in the developing embryo.

这个尿囊结构对于发育中的胚胎的废物储存至关重要。

7.The allantoid is derived from the mesoderm layer of the embryo.

尿囊源自胚胎的中胚层。

作文

The study of embryology reveals many fascinating structures that play crucial roles in the development of vertebrates. One such structure is the allantoid, which is an important part of the extra-embryonic membranes in reptiles, birds, and mammals. The allantoid serves various functions during the developmental stages of these organisms, and understanding its role can provide insights into evolutionary biology and comparative anatomy.In reptiles and birds, the allantoid is primarily involved in the storage of nitrogenous waste. As the embryo develops, it produces waste products that need to be managed efficiently. The allantoid acts as a reservoir for these wastes, preventing toxicity within the developing embryo. This function is particularly vital in egg-laying species where space is limited. Moreover, the allantoid is also involved in gas exchange, facilitating the transfer of oxygen and carbon dioxide between the embryo and the external environment. This dual role underscores the significance of the allantoid in ensuring the embryo's survival and proper growth.In mammals, the allantoid has a slightly different function. While it still plays a role in waste management, it also contributes to the formation of the umbilical cord. During the early stages of development, the allantoid extends into the chorion, forming a structure that connects the embryo to the placenta. This connection is essential for nutrient and gas exchange between the mother and the developing fetus. The allantoid thus plays a critical role in the establishment of the placental circulation system, highlighting its importance in mammalian reproduction.The evolutionary significance of the allantoid cannot be overlooked. It is believed that the presence of the allantoid in higher vertebrates represents an adaptation that allows for more efficient waste management and nutrient exchange. This adaptation may have been a key factor in the successful colonization of terrestrial habitats by vertebrate species. By studying the allantoid and its variations across different species, scientists can gain a better understanding of how evolutionary pressures shape developmental processes.Furthermore, the allantoid has implications in medical research. Understanding its structure and function can provide insights into congenital disorders related to embryonic development. Abnormalities in the formation or function of the allantoid can lead to complications in pregnancy or developmental issues in infants. Therefore, research on the allantoid not only enhances our knowledge of basic biology but also has practical applications in medicine and reproductive health.In conclusion, the allantoid is a remarkable structure with diverse functions across various species. Its roles in waste management, gas exchange, and placental development illustrate its significance in embryonic development. By exploring the allantoid, we can uncover valuable information about evolutionary biology and improve our understanding of human health. The study of this fascinating structure continues to be an important area of research in both biology and medicine, reflecting the intricate connections between development, evolution, and health.

胚胎学的研究揭示了许多在脊椎动物发育中发挥关键作用的迷人结构。其中一个结构是尿囊，它是爬行动物、鸟类和哺乳动物的额外胚胎膜的重要部分。尿囊在这些生物的发育阶段中发挥着各种功能，理解其作用可以为进化生物学和比较解剖学提供见解。在爬行动物和鸟类中，尿囊主要参与氮废物的储存。随着胚胎的发展，它会产生需要有效管理的废物产品。尿囊作为这些废物的储存库，防止在发育中的胚胎内产生毒性。这一功能在卵生物种中尤为重要，因为空间有限。此外，尿囊还参与气体交换，促进氧气和二氧化碳在胚胎和外部环境之间的转移。这一双重作用凸显了尿囊在确保胚胎生存和正常生长方面的重要性。在哺乳动物中，尿囊的功能略有不同。虽然它仍然在废物管理中起作用，但它也有助于脐带的形成。在早期发育阶段，尿囊延伸到绒毛膜中，形成一个将胚胎与胎盘连接的结构。这一连接对于母体与发育中的胎儿之间的营养和气体交换至关重要。因此，尿囊在胎盘循环系统的建立中发挥着关键作用，突显了它在哺乳动物繁殖中的重要性。尿囊的进化意义不容忽视。据信，高等脊椎动物中尿囊的存在代表了一种适应，使得废物管理和营养交换更加高效。这种适应可能是脊椎动物成功征服陆地栖息地的关键因素。通过研究尿囊及其在不同物种间的变异，科学家可以更好地理解进化压力如何塑造发育过程。此外，尿囊在医学研究中也有重要意义。了解其结构和功能可以为与胚胎发育相关的先天性疾病提供见解。尿囊的形成或功能异常可能导致妊娠并发症或婴儿发育问题。因此，关于尿囊的研究不仅增强了我们对基础生物学的理解，而且在医学和生殖健康方面具有实际应用。总之，尿囊是一个具有多样化功能的非凡结构，在不同物种中发挥着重要作用。它在废物管理、气体交换和胎盘发育中的作用展示了它在胚胎发育中的重要性。通过探索尿囊，我们可以揭示有关进化生物学的宝贵信息，并改善我们对人类健康的理解。对这一迷人结构的研究继续成为生物学和医学中一个重要的研究领域，反映了发育、进化和健康之间的复杂联系。