Aging; Caenorhabditis elegans/physiology; Electron Transport; Mitochondria/metabolism; Oxygen Consumption; Animals; Behavior, Animal; Caenorhabditis elegans/cytology; Caenorhabditis elegans/growth & development; Caenorhabditis elegans Proteins/genetics; Caenorhabditis elegans Proteins/metabolism; Cell Size; Electron Transport Complex I; Electron Transport Complex III/genetics; Electron Transport Complex III/metabolism; Electron Transport Complex IV/genetics; Electron Transport Complex IV/metabolism; Endoribonucleases/genetics; Endoribonucleases/metabolism; Feeding Behavior; Forkhead Transcription Factors; Iron-Sulfur Proteins/genetics; Iron-Sulfur Proteins/metabolism; Longevity; Mitochondrial Proton-Translocating ATPases/genetics; Mitochondrial Proton-Translocating ATPases/metabolism; Movement; NADH Dehydrogenase/genetics; NADH Dehydrogenase/metabolism; NADH, NADPH Oxidoreductases/genetics; NADH, NADPH Oxidoreductases/metabolism; Phenotype; RNA Interference; RNA, Double-Stranded/genetics; RNA, Double-Stranded/metabolism; RNA, Messenger/genetics; RNA, Messenger/metabolism; Receptor, Insulin/genetics; Receptor, Insulin/metabolism; Ribonuclease III; Transcription Factors/genetics; Transcription Factors/metabolism