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.
Street light. For other uses, see Streetlight (disambiguation). A street light, light pole, lamppost, street lamp, light standard, or lamp standard is a raised source of light on the edge of a road or walkway. Modern lamps may also have light-sensitive photocells that activate automatically when light is or is not needed: dusk, dawn, or the onset of dark weather.