pseudopodium

简明释义

英[ˌsjuːdə(ʊ)ˈpəʊdɪəm]美[ˌsjʊdəˈpodɪəm]

n. 虚足；[植] 假足

复 数 p s e u d o p o d i a

英英释义

单词用法

同义词

反义词

例句

1.The amoeba extends its pseudopodium to engulf food particles.

变形虫伸出它的伪足来吞噬食物颗粒。

2.During locomotion, the pseudopodium helps the cell to move forward.

在运动过程中，伪足帮助细胞向前移动。

3.Researchers observed how the pseudopodium forms in response to environmental stimuli.

研究人员观察到伪足如何对环境刺激作出反应。

4.The pseudopodium is crucial for phagocytosis in certain immune cells.

伪足对某些免疫细胞中的吞噬作用至关重要。

5.In some protozoa, the pseudopodium can also serve as a sensory structure.

在某些原生动物中，伪足也可以作为感知结构。

作文

In the world of biology, there are many fascinating structures and mechanisms that allow organisms to interact with their environment. One such structure is the pseudopodium, which plays a crucial role in the movement and feeding of certain cells, particularly amoebas. The term pseudopodium derives from Greek, meaning 'false foot,' and it aptly describes the temporary extensions of the cell membrane that these organisms use to propel themselves and capture food. The pseudopodium is not a fixed structure; instead, it forms and retracts as needed. This dynamic ability allows amoebas to navigate through their surroundings by extending a part of their cytoplasm in the direction they wish to move. When the pseudopodium reaches the desired location, the rest of the cell body flows into it, effectively allowing the organism to 'crawl' along surfaces. This form of locomotion is known as amoeboid movement, which is characterized by the fluidity and flexibility of the cell's shape. In addition to movement, pseudopodia serve another essential function: feeding. Many protozoans, like amoebas, use their pseudopodia to engulf food particles through a process called phagocytosis. When an amoeba encounters a food source, it extends its pseudopodium around the particle, eventually enclosing it within a food vacuole. This allows the organism to digest the food internally, providing it with the necessary nutrients for survival. The ability to manipulate their environment using pseudopodia is a remarkable adaptation that has allowed these single-celled organisms to thrive in diverse habitats, from freshwater ponds to soil. Interestingly, the concept of pseudopodia is not limited to just amoebas. Other organisms, including certain white blood cells in humans, also utilize similar structures for movement and capturing pathogens. For instance, macrophages, a type of immune cell, extend their pseudopodia to engulf bacteria and other foreign invaders, playing a vital role in the immune response. This similarity across different species highlights the evolutionary significance of pseudopodia as a functional adaptation for survival. In conclusion, the pseudopodium is a fascinating example of how simple cellular structures can have profound implications for movement and feeding in various organisms. Its versatility enables cells to adapt to their environments, whether it be for locomotion or the acquisition of nutrients. Understanding the role of pseudopodia not only provides insight into the lives of single-celled organisms but also underscores the intricate connections between structure and function in biology. As we continue to explore the microscopic world, the study of pseudopodia and their functions will undoubtedly reveal even more about the complexity and diversity of life on Earth.

在生物学的世界里，有许多迷人的结构和机制，使生物体能够与环境相互作用。其中一个结构就是伪足，它在某些细胞的运动和摄食中发挥着至关重要的作用，特别是变形虫。术语伪足源自希腊语，意思是“假脚”，它恰当地描述了这些生物用来推动自己和捕捉食物的细胞膜的临时延伸。 伪足不是一个固定的结构；相反，它会根据需要形成和收缩。这种动态能力使变形虫能够通过在它们希望移动的方向上扩展细胞质的一部分来导航。当伪足到达所需位置时，细胞体的其余部分流入其中，从而有效地使生物体在表面上“爬行”。这种运动形式被称为变形运动，其特点是细胞形状的流动性和灵活性。 除了运动之外，伪足还具有另一项基本功能：摄食。许多原生动物，如变形虫，利用它们的伪足通过一种称为吞噬作用的过程来吞噬食物颗粒。当变形虫遇到食物来源时，它会将其伪足扩展到颗粒周围，最终将其包裹在食物泡内。这使得生物体能够在内部消化食物，为其生存提供必要的营养。能够利用伪足操纵环境是一种显著的适应，使这些单细胞生物能够在从淡水池塘到土壤等多种栖息地中繁衍生息。 有趣的是，伪足的概念并不仅限于变形虫。其他生物，包括人类的某些白血球，也利用类似的结构进行运动和捕获病原体。例如，巨噬细胞，一种免疫细胞，通过扩展其伪足来吞噬细菌和其他外来入侵者，在免疫反应中发挥着重要作用。这种不同物种之间的相似性突出显示了伪足作为生存功能适应的进化重要性。 总之，伪足是一个迷人的例子，展示了简单的细胞结构如何对各种生物的运动和摄食产生深远的影响。它的多功能性使细胞能够适应其环境，无论是为了运动还是获取营养。理解伪足的作用不仅提供了对单细胞生物生活的深入了解，还强调了生物学中结构与功能之间的复杂联系。随着我们继续探索微观世界，对伪足及其功能的研究无疑将揭示更多关于地球生命复杂性和多样性的信息。