mesembryo

例句：

1. 1. The embryonic development of the fetus is crucial to its survival.
   胎儿的胚胎发育对其生存至关重要。
2. 2.The study of mesembryos has led to new insights into the origins of life.
   对胚囊的研究为生命起源的新见解提供了线索。
3. 3.During the early stages of development, the mesembryos are surrounded by a sac of fluid.
   在发育的早期阶段，胚囊被一种液体囊包围。