胚珠是半球形的，有2个被膜，腱鞘状，而原孢子细胞直接作为大孢子母细胞起作用。
The ovules are hemitropous, with 2 integuments, tenuinucellate and the archesporial cell functions directly as the mega-spore mother cell.
大多数被子植物的胚珠有两层珠被，而裸子植物通常只有一层。
Most angiosperm ovules possess two integuments, while gymnosperms usually have only one.
当胚珠的方向是直生胚珠时，合点和珠柄连成一条直线，当胚珠是倒生胚珠或弯生胚珠时，合点和珠柄之间有一定的距离。
When ovule orientation is orthotropous the chalaza corresponds to the point where the funicle is attached but in anatropous and campylotropous ovules the chalaza is some distance from the funicle .
近年来，随着研究手段的不断改进，研究者对许多关键性的问题，如胚珠的起源、胚珠发生发育的分子机制已经有了一定的认识，但是这些问题并未得到圆满的解决。
The development of research has resolved in part many important problems, such as the origin and molecular mechanism of ovule ontogenesis. But these problems still require further study.
近年来，随着研究手段的不断改进，研究者对许多关键性的问题，如胚珠的起源、胚珠发生发育的分子机制已经有了一定的认识，但是这些问题并未得到圆满的解决。
The development of research has resolved in part many important problems, such as the origin and molecular mechanism of ovule ontogenesis. But these problems still require further study.
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