ABSTRACT
Environmental stressors exhibit their adverse effects at different levels of organization, such as populations, individual organisms, tissues, and cells. At the individual level, these effects are demonstrated in the life-history traits of an organism, such as development, growth, aging, longevity, survival, and reproduction. This chapter describes the processes of aging and cell death. One aim will be to translate the process of aging at the cellular level to the organism level. Aging is considered a continuous process, which proceeds during an organism’s life, including developmental stages, such as metamorphosis of insects. Environmental stress contributes to the aging process, and even if the damage were completely removed, the cost of an increased metabolic rate to abolish the stress and repair the damage leads to increased aging. Environmental stress contributes to the aging process by increased cellular deterioration. The stress defense systems mentioned above try to abolish these effects, but even if they do, it is at a cost.
