Fig. 8. Gap junctions between germline stem cell and cap cell viewed by electron microscopy. Scale bar=100 nm. (A) Low-magnification infiltrated with lanthanum, showing the spectrosome (Sp) of the stem cell (lower cell) and the adjacent cap cell (upper cell) with a prominent Golgi apparatus (G). Gap junction (arrow). (B) Higher magnification of A. Gap junction with characteristic 2x10^–9 m (20 Å) spacing (arrow). Wide lanthanum-filled intercellular space (arrowheads in B and C) (>200 Å; 2x10^–8 m) adjacent to gap junction. (C) A second germarium, fixed without lanthanum, showing a gap junction (arrow) between a stem cell (below) and cap cell (above).