Complex V (F0F1−ATP synthase) is the "hydroelectric turbine" that makes use of the power of the proton move into the matrix via the "turbine" to synthesize ATP. The ATP synthase (Complex V) "rotary motor" is the smallest recognized natural nanomachine. The mitochondria are capsule-formed cellular organelles that generate power (ATP molecules) from aerobic (oxygen-utilizing) metabolism using respiratory chain and ATP synthase enzymes. Mitochondria are the only cellular organelles with their own DNA. Each mitochondrion contains 2-to-12 equivalent copies of mitochondrial DNA (2-to-12 circular strands). The "viscious cycle" idea that free radical harm to mitochondrial DNA results in mitochondria that produce extra superoxide has been questioned. Hawkfish exhibit much more fluidity; mature females typically develop into male, but have been observed to switch again if the situations change. Diseases attributable to mutated mtDNA have the greatest impact on cells producing the most energy - cells of mind and muscle - therefore mitochondrial diseases are often encephalomyopathies . Vitamin C acts as an anti-oxidant in the non-lipid ("watery") parts of cells, between cells and within the bloodstream.