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Section 4 Cellular Aging. A number of cellular functions decline progressively with age. Mechanism. A progressive accumulation of sublethal injury that compromises cellular function and may lead to cell death, or at least to diminished capacity of cells to respond to injury. . Mechanism.
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Section 4 Cellular Aging A number of cellular functions decline progressively with age
Mechanism • A progressive accumulation of sublethal injury that compromises cellular function and may lead to cell death, or at least to diminished capacity of cells to respond to injury.
Mechanism • Mitochondrial oxidative phosphorylation is reduced, as is synthesis of structural, enzymatic, and receptor proteins. • Senescent cells have a diminished capacity for nutrient uptake and for repair of chromosomal damage.
The morphologic alterations • in senescent cells include atrophy, accumulation of lipofuscin pigment pleomorphic vacuolated mitochondria, diminished endoplasmic reticulum, distorted Golgi apparatuses. reduced synthesis of structural, enzymatic, and receptor proteins
characteristic • Universality • Progressing, irreversible • internal cause • baneful
Theory • Genetic programmed theory: Incomplete replication of chromosome ends. Clock genes. • Error accumulating theory