| Abstract: | A freeze-fracture study has revealed rod-shaped intramembra-nous particles on the plasma membrane P-face (cytoplasmic leaflet) of the mi-tochondria-rich cell (or flask cell) of Xenopus laevis and Rana ridibunda epidermis. Such particles have previously been found in all other mitochondria rich cells examined by this technique, namely, the MR-cell of toad bladder epi-thelium, the dark cèll of rat kidney collecting tubule, and the flask cell of Xenopus kidney collecting tubule. These particles are assumed, therefore, to be closely connected with the function of this cell type. |
