囊状鞭毛虫类

例句：

1. 1.The study of protozoa is crucial for understanding the diversity of life on Earth.
   研究原生动物对于理解地球上生物多样性至关重要。
2. 2.In the cyclopedia, there are many species of protozoa that can be found in different environments.
   在《原生动物学》一书中，可以找到许多可以在不同环境中生存的原生动物种类。
3. 3. Protozoa play a significant role in the ecosystem, as they help to break down organic matter and contribute to nutrient cycling.
   原生动物在生态系统中起着重要作用，因为它们帮助分解有机物并参与营养物质循环。