The areas of the tongue sensitive to tastes. The classical theory about the physiology of taste recognizes the existence of four fundamental tastes - sweet, salty, sour and bitter - each being perceived by specific areas of the tongue by means of gustatory receptors, also known as taste buds.
Theories of Aging. Theories of Aging. Erik Erikson, who took a special interest in this final stage of life, concluded that the primary psychosocial task of late adulthood (65 and beyond) is to maintain ego integrity (holding on to one's sense of wholeness), while avoiding despair (fearing there is too little time to begin a new life course).
Entropy is often cited as requiring aging. Stochastic theories of aging similarly propose that aging is the result of inevitable small random changes that accumulate with time. Entropy, in this context, refers to the tendency of all matter to decay into a more random, less ordered state.he sort of experiences we describe here are very similar to the experience of human aging. In fact, we use the same word, aging, to describe gradual deterioration in humans, automobiles, or exterior paint, and many people think of biological aging as a wearing out process.