Tangential cuts through alveolar type II cell granules show dense outer layers of this regularly arranged molecular substructure, has a periodicity to it, albeit densities of a different size than at other sites in the , just like the less dense middle band of these granules. Images below also show a slight tendency for vertical banding, within the horizontal layers of the surfactant protein (A ? ) granule. The hierarchy for all the level of substructural organization are here:
- 100 nm period (height) (no restriction on length of granule seen) which has 1,3,5 or 7 layers between the outer dense bands
- Outer dense layers on perpendicular cut look continuous, on tangential cut however, they show a periodicity with large round densities about 2.5 per 100 nm length.
- Moderately dense central band shows a periodicity of 5-7 densities per 100 nm
- vertical stripes, a kind of banding, perpendicular to the long orientation of mos that coinciding with the periodicity of the central dense band.
Negative 7088_23356)ferret_#17
