Life in the Later Years - Essay Example

Life in the Later Years There are several different theories that seek to explain why people age, the theories are categorized into three major categories. The first of these theories is programmed theory of aging. There are three sub-categories of this theory; the programmed longevity, which indicates that aging, occurs as a process of switching of certain genes. The second sub-category is the endocrine theory. This states that aging is because of a biological clock that is governed by hormones.

The third subcategory of the programmed aging theory is the immunological theory, which states that aging is because of the decline in the immune system ability to protect the body against diseases. This means that as one ages, the vulnerability to diseases that cause cell death and aging increases (Gavrilov and Gavrilova, 339-356).The second major category of aging theories is the error theory, which is represented by the phenomenon of wear and tear. According to this theory, aging is a result of wear and tear of cells and tissues with prolonged use.

This wear and tear eventually kills the cells. Being the basic units of life the death of the cells leads to death of the body (Gavrilov and Gavrilova, 339-356). The theory, therefore, compares the body to a machine that undergoes wear and tear as it ages.The cross-linking theory is another aging theory. The theory suggests that throughout life, the body accumulates cross-linked proteins. These proteins continuously interact and form complex compounds with other body substances. The reactions cause cells and tissues changes that are associated with aging (Gavrilov and Gavrilova, 339-356).

Work citedGavrilov, Leonid A, and Natalia S Gavrilova. “Evolutionary Theories of Aging and Longevity.” TheScientificWorldJournal 2 (2002): 339–356.