The function of the echinoderm madreporite.

对棘皮动物的功能进行了研究，重点研究了毛道纤毛上皮双向运输的机制和可能的分选机制。通过胶原酶处理从硅灰石中分离出的孔管的开口附近注射的微珠的运动的DIC显微镜显示，直径大于0.5um的微珠总是向口腔方向输送，而较小的微珠(&lt；0.2um)通常向相反的方向移动，这表明根据大小进行选择。切开分离的孔管获得的纤毛上皮的平面上也观察到双向运输。这表明，双向性不是由组织的管状几何形状引起的，而是纤毛的固有特征。然而，对单个纤毛运动的观察表明，它们的拍子形状类似于典型的纤毛。

The function of the echinoderm madreporite was studied with a focus on the mechanism of the bidirectional transport by the ciliated epithelium of the pore canal and the possible sorting mechanism. DIC microscopy of the movement of microbeads injected near the openings of pore tubes isolated from the madreporite by collagenase treatment revealed that the beads larger than 0.5 mum in diameter were always transported oralwards whereas the smaller beads (<0.2mum) often moved in the opposite direction, indicating selection by size. Bidirectional transport was also observed on the flat surface of ciliated epithelium obtained by cutting open an isolated pore tube. This showed that the bidirectionality did not arise from the tubular geometry of the tissue but an inherent characteristic of the cilia. Observation of the movement of individual cilia indicated, however, that their beat form was similar to that of typical cilia.