Gravel areas where there is little traffic. Globally, far more roads are surfaced with gravel than with concrete or tarmac; Russia alone has over of gravel roads. Both sand and small gravel are also important for the manufacture of concrete. Large gravel deposits are a common geological feature, being formed as a result of the weathering and erosion of rocks. The action of rivers and waves tends to pile up gravel in large accumulations. This can sometimes result in gravel becoming compacted and lithified into the sedimentary rock called conglomerate. Where natural gravel deposits are insufficient for human purposes, gravel is
Granular corneal dystrophy autosome), and only one copy of the gene is sufficient to cause the disorder, when inherited from a parent who has the disorder. The gene TGFBI encodes the protein keratoepithelin. Corneal transplant is not needed except in very severe and late cases. Light sensitivity may be overcome by wearing tinted glassess. Granular corneal dystrophy Granular corneal dystrophy is a slowly progressive corneal dystrophy that most often begins in early childhood. Granular corneal dystrophy has two types: Granular corneal dystrophy is diagnosed during an eye examination by an ophthalmologist or optometrist. The lesions consist of central, fine, whitish granular lesions in