二分体一对由四分体在成熟分裂过程中形成的同源染色体
高度演化的黄山A型花岗岩：对扬子克拉通东南部中生代岩石圈减薄的约束？。
二分体、四分体和小孢子时期，细胞内普遍观察到微核，且出现大量异形细胞。
1·Megaspore tetrad is linear. The chalazal megaspore develops into an embryo sac of Polygonum type.
大孢子四分体为线形，合点端功能大孢子发育成为蓼型胚囊。
2·This phenomenon occurs in the early tetrad stage.
这个现象在早期四分体阶段出现。
3·Abnormal development was observed at tetrad and mature embryo sac.
在四分体和成熟胚囊时期观察到了异常发育现象。
4·The micronuclei were not observed in tetrad stage.
四分体阶段无微核出现。
5·Micronuclei were observed in the tetrad stage.
四分体阶段有微核。