Answer: The Generalised Slowing Hypothesis Theory
Explanation:
The Generalised Slowing Hypothesis is built upon wide observations in many studies of age related slowing and suggests that it is the primary contributor to the declines in cognitive functioning seen with aging.
As people age, B lymphocytes and T lymphocytes become less active. These cells secrete antibodies and are thus crucial to the immune system. T cells are made in the thymus which shrinks as aging occurs. Thus reducing the body's ability to fight infections as aging occurs.
Through the normal aging process, DNA is damaged by environmental factors such as pollutants and toxic agents. As a result, there is deletions of genetic material and mutations in DNA replicated in new cells. Reduced functioning in cells and tissues occur when these errors accumulate.
Also as aging occurs, glucose molecules attach themselves to proteins and form cross links. These crosslinks reduce the flexibility of tissues making them become stiff. The circulatory systems becomes less efficient since the tissues of the lungs, heart and arteries lose flexibility.