Final answer:
Mitochondria contribute to aging and disease in humans through oxidative stress caused by reactive oxygen species. Mitochondrial dysfunction can result in a wide range of symptoms and diseases, including arthritis, memory issues, some cancers, and neurological disorders.
Step-by-step explanation:
Mitochondria are believed to make an important contribution to aging and disease in humans because of the free radical theory of aging. This theory suggests that accumulated cellular damage from oxidative stress, caused by reactive oxygen species, contributes to the physiological and anatomical effects of aging. Research has shown that reducing oxidative damage can result in a longer lifespan in certain organisms, while increasing oxidative damage can shorten lifespan. Mitochondrial dysfunction can lead to a wide range of symptoms and diseases, including arthritis, memory issues, some cancers, and neurological disorders.