梨形

The toxicity of mercury ion and pesticide cy-permethrin to tetrahymena pyriformis was observed in this study according to the method of aquatic toxicology.

采用梨形四膜虫为实验生物评价了汞离子和安绿宝农药的毒性。

There are 5 stages during the development of embryo, including the stage of 2-celled proembryo, multicellular proembryo, globular proembryo, pyriform proembryo, differential embryo and mature embryo.

育经过二胞、多胞、球形、梨形、化和成熟阶段。