ultra[nanno] plankton

例句：

1. 1. The ultra-small size ofthese plankton makes them difficult tospot in the water.
   这些浮游生物的超小尺寸使得它们在水中难以被发现。
2. 2.The plankton play a crucial rolein maintaining the balance of marine ecosystems.
   浮游生物在维持海洋生态系统平衡中起着至关重要的作用。
3. 3. The study of ultra-small plankton could lead to newdiscoveries about the origins of lifeon Earth.
   研究超微型浮游生物可能会带来关于地球上生命起源的新发现。