title: Layered membranes: a diffusion barrier to gases in teleostean swimbladders.
abstract: Flattened cells are dispersed in an overlapping fashion within the submucosa of closed (physoclistous) swimbladders. Within the cells are located round platelets best seen by phase or interference type microscopy. At the electron microscope level the platelets are revealed as repeated, numerous layers of membranous discs. Each disc is a bilayer with an enlarged rim. The bilayer is strongly and preferentially reactive to osmium tetroxide. Swimbladder walls are known to be highly resistant to passage of gases. The randomly disposed platelets with the highly ordered layering of membranes may provide that physical resistance to gas movement.
mesh_terms: D000400:Air Sacs / Q000502:physiology / Q000648:ultrastructure*; D000818:Animals; D005399:Fishes / Q000033:anatomy & histology*; D005740:Gases; D008566:Membranes / Q000648:ultrastructure
chemical_list: D005740:Gases