Occluding junctions in Sertoli cells of ram and rat testis. Multiple focal sites of membrane fusion are indicated by arrows in each panel. Underlying these sites, associated bundles of filaments and...

Epithelia of invertebrates contain zona continua and septate junctions not found in mammals. Left, zonula continua from gut epithelium of a flea; right, septate junction from the midgut epithelium of...

Freeze-fracture preparation of a continuous junction on the lateral surface of epithelial cells from the gut of a flea. Meandering ridges appear to be on the P-face of the replica. Figure 80, by Susu...

Upper: capillary endothelial cell junction in the rete mirabile of the gas bladder of the toadfish Opsanus tau shows dense intracelluular plaques and the central dense line in the intercellular space,...

These examples of ependymal epithelium from the rat brain represent epithelia that lack zonulae occludentes. Further, there appears to be no consistent order to the junctional specializations that are...

Representative examples of gap junctions from vertebrates (ciliary epithelium from the eye of a Macaca mulatta, upper) and invertebrates (inverted gap junctions from cells of the mid-gut of the horses...

Replica of a freeze-fractured gap junction presents the inner half-membrane on one of the cells (P-face, lower half of the micrograph) and the the outer half-membrane of the other cells (E-face, upper...

Upper panel shows a typical zonula occludens of rat intestinal epithelium, prepared using freeze fracture techniques. A network of intersecting strands on the P-face, and a complementary pattern of g...

A freeze fracture replica of a Sertoli cell junction from rat testis shows more than 50 rows of particles along the E-face. Image from Gilula, Fawcett and Aoki, Dev. Biol. 50: 142-168 (1976), reprint...

Freeze-fracture images of continuous junctions along epithelial cells from the midgut of Rhodnius prolixus. Figures 78 (upper) and 79 (lower) by Nancy Lane, from Chapter 3 (Junctional Specializations...

Figures 81 (upper) and 82 (lower) from Chapter 3 (Junctional Specializations) of 'The Cell, 2nd Ed.' by Don W. Fawcett M.D. Septate junctions (upper, rectum; lower, testis) in the cockroach Periplane...

Electron micrograph of the junctional complex of intestinal epithelial cells of the rat shows the apical-most zonula occludens (tight junction), the zonula adherens (medium junction) and the macula ad...

Freeze fracture replica of zonula occludens junctions from the small intestine of a Xenopus laevis tadpole. The occluding junction appears as a meshwork of ridges on the P-face or a corresponding pa...

Sertoli-Sertoli occluding junctions from guinea pig testis. Figures 67 (left) and 68 (right) from Chapter 3 (Junctional Specializations) of 'The Cell, 2nd Ed.' by Don W. Fawcett M.D. A PDF copy of t...

Glial cells in the nerve cord of the annelid worm, Aphrodita aculeata are rich in 10 nm filaments, and desmosomes are abundant. Figure 89 from Chapter 3 (Junctional Specializations) of 'The Cell, 2nd ...

Upper: a gap junction on the boundary between two hepatic cells shows a typical narrow and straight interface. Lower: in some preparations, gap junctions appear curved, and project into one of the ce...

Stratified squamous epithelium from the esophagus of the rat. Keratin filaments (tonofilaments, arrows) are sparse, and desmosomes are few (see inset), in the basal cell layer of this tissue. Figures...

Papillary muscle from cat heart shows a step-like end-to-end junction of two cardiac muscle cells. The longitudinally oriented lateral cell boundaries are straight and exhibit extensive gap junctions...

Gap junctions in papillary muscle from cat heart. These communicating junctions are responsible for the spreading wave of depolarization through the myocardium. Desmosomes can also be found on the l...

Typical organization of gap junctions as seen in thin sections (upper) and replicas of freeze-fractured cell membranes (middle and lower). Upper, gap junction from the saccular macula of a goldfish; ...

Gap junctions isolated from mouse liver and negatively stained with uranyl formate. At higher magnification, the 8-9 nm particles, or connexons, have a central 1.5-2 nm electron dense pore. Images b...

Images of desmosomes from conventional EM and freeze fracture preparations show transmembrane filaments that link two hemidesmosomes. Upper: section of a cell boundary in the ciliary epithelium of th...

Upper panel, adjoining portions of two cells in the stratum spinosum of hamster cheek pouch epithelium shows desmosome junctions between two cells. Lower, a portion of the basal surface of a cell in ...

Freeze fracture replicas of zonula occludens junctions from the large intestine of a tadpole (upper) and intestine of a post-metamorphic toad (lower). The occluding junction appears as a meshwork of...

Gap junctions from a granulosa cell of a rat ovarian follicle. Variability in size of the gap junctions is likely an artifact of the freeze fracture preparation. Figure 99 from Chapter 3 (Junctional ...

Gap junctions in ciliary epithelium under conditions of oxygenation (upper) and anoxia (lower), in tissue prepared by ultrarapid freezing using liquid helium. Under oxygenated conditions, the connexo...