Source:http://linkedlifedata.com/resource/umls/id/C1166988
GO: A three dimensional regular lattice found in etioplasts. It is composed of a continuous system of tubules but when exposed to light the symmetrical arrangement is rapidly lost as tubules become pinched off into two dimensional sections of lattice. These for perforated sheets of membrane that move apart, extend and increase, finally establishing the typical granal and intergranal lamellae of the mature chloroplast. [ISBN:0140514031]