外珠被

珠孔由内珠被和腹侧外珠被构成。

The micropyle is formed with inner integuments and partial outer integument .

棉花纤维细胞是棉花胚珠外珠被表皮细胞经分化突起和极性伸长而成的单细胞。

Cotton fiber cell is single-celled and originates from the epidemic of the outer integument of ovule .

胚珠直生，厚珠心，珠心被内、外珠被以及盖被等三层被膜所包围。

The ovule is orthotropous and crassinucellate , nucellus is surrounded by three envelopes .

此时，外珠被发育形成外种皮，褐色肉质；内珠被形成内种皮，石质化、坚硬。

At this moment , the exterior integument develops the testa which is brown and fleshy ; the inner integument develops the endothelium which is hard . 2 .

当果实发育成熟时，外珠被内表皮细胞的细胞壁加厚明显且石质化，外珠被内的薄壁细胞增殖并纵向延长增大。

When the fruit matures , cell walls of inner epidermis cells of exterior integument become thick and lithoid obviously , and parenchyma cells of exterior integument multiply and extend .

棉纤维由棉花胚珠外珠被表皮层的单细胞发育而成，属于种子表皮毛，其分化和发育过程由四个相互重叠的时期组成。

Fibers are the seed hairs of cotton , and they originate from the epidermal cells of the ovular surface . Fiber development is composed of four distinct and overlapping stages .

棉纤维是由棉花胚珠外珠被表皮层的单细胞分化发育而成的，成熟期棉纤维的纤维素含量几乎占细胞壁的95%，因此棉纤维是研究高等植物纤维素生物合成的理想材料。

Cotton fibers , originated from the epidermal cells of the ovular surface , contain almost 95 % cellulose in the matured cell walls , which are considered as ideal materials for cellulose biosynthesis experiment .

棉花纤维是胚珠外珠被表皮细胞发育延伸而成的表皮毛，棉花纤维细胞的发育与拟南芥表皮毛发育模式相似。

The study reveals that cotton fiber is epidermal hair , epidermal cell of ovule outer integument from cotton fiber . And cotton fiber cell possesses the similar molecule regulating mode as the growth of epidermal hair cell in Arabidopsis .