pansporoblast

例句：

1. 1. Pansporoblasts are the first stage of embryonic development.
   卵黄囊是胚胎发育的第一阶段。
2. 2. The pansporoblast is responsible for producing the nutrient-rich fluid that nourishesthe developing embryo.
   卵黄囊负责产生滋养正在发育胚胎的营养丰富的液体。
3. 3.During the early stages of pregnancy, the pansporoblast plays a crucial role in the formation of the placenta.
   在怀孕早期，卵黄囊在形成胎盘中起着至关重要的作用。