Chapter 3 Flashcards
expression of declining functional capacity of most basic structures in cells, which in turn affects functioning of organisms
biological aging
measured by age graded behaviors, carrying expected status and role within a particular culture or society
social age
a complex genetically regulated interactive process of change in every living organism
biological aging “senescence”
changes to cell that decrease ability to replicate attributed to aging
cellular functioning
major biological questions
- what triggers process of aging?
2. can it be stopped or modulated?
suggest that aging is the result of predictable cellular death
-biological clock
programmed theories of aging
predetermined lifespan
biological clock
explains aging as a programmed decline in the functioning of the immune nervous, and endocrine systems
Neuroendocrine control or pacemaker theory
cells lose their ability to reproduce
replicative senescence
aging is a programmed accumulation of damage and decline in the function of the immune system
-damage is a result of oxidative stress
immunity theory
aging is the result of an accumulation of random errors in the synthesis of cellular dna and rna
error theories
cellular errors a result of wearing out over time from continued use
- a progressive decline in cellular function or increased cellular death
- internal and external pollutants
1. pollutants
2. metabolic by-product
wear and tear theory
aging is a product of accumulated damage from errors associated with cross-linked proteinss
-initiated by blood glucose linking with protein in process of glycosylation or glycation
cross-linkage theory
- cellular errors are a result of random damage from free radicals
- referred to as “oxidative stress” or “oxidative damage”
- mitochondrial dna most affected by these changes
oxidative stress theory “free radical theory”
repeated sequences on chromosomes essential for cellular reproduuction
- shorten with every cell cycle
- hypothesized to be contributory to senescence of the cells
telomeres