Mitochondrial disease is a group of disorders caused by dysfunctional mitochondria, the organelles that generate energy for the cell.itochondrial diseases are sometimes (about 15% of the time) caused by mutations in the mitochondrial DNA that affect mitochondrial function.
1 Surface-mounted light â the finished housing is exposed, not flush with surface. 2  Chandelier. 3  Pendant light â suspended from the ceiling with a chain or pipe.  Sconce â provide up or down lights; can be used to illuminate artwork, architectural details; commonly used in hallways or as an alternative to overhead lighting.
If necessary for visual balance, lights may be placed higher when doors are very tall. A more harmonious and better-lit effect may be produced by increasing the size, rather than the height, of the fixtures. Occasionally, an overhead or pendant light is most effective for illuminating taller-than-average doors.