“珠被”造句
某些植物的
珠被和珠心细胞形成完全正常的胚.
The cells of the integument and nucellus of some plants form perfectly normal embryos.
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.
外种皮:覆盖在种子外部的坚硬干燥的保护层, 由胚珠的
珠被发育形成.
Testa The hard dry protective covering of a seed, formed from the integuments of the ovule.