n.中胚层
It is involved in mesoderm formation and left-right axis determination. 它与胚胎中胚层的形成以及左右体轴的决定有关。
Fibroblasts are mesenchymal cells, which are derived from the embryonic mesoderm. 成纤维细胞是来源于胚胎中胚层的间充质细胞。