Microvilli, Brush Border-Jejunum

Freeze-fracture image of microvilli (brush border) from the apical portion of an epithelial cell of the small intestine. In the freeze-fracture technique, membranes are split into two membrane complements.  This makes it possible to investigate and interpret the structures of the two complementary inner membrane surfaces. It is hardly possible to render a picture of the real outer and inner surfaces of the plasmalemma with the freeze-etching technique alone. The freeze-fracture technique exposes the extracellular face ( EF) and the protoplasmic face (PF) 2 . EF is the expose d face of the half-membrane that started out as the border to the extracellular space; PF was the half-membrane toward the cytoplasmic side .

Jejunal enterocytes.

1 Extracellular face (EF)

2 Protoplasmic face (PF)

3 Apical cytoplasm, location of the terminal web

Electron microscopy; magnification: × 35 200

References

Kuehnel, W.(2003). Color Atlas of Cytology, Histology, and Microscopic Anatomy. 4^th edition . Institute of Anatomy Universitätzu Luebeck Luebeck, Germany . Thieme Stuttgar t · New York .