The progressive incremental transformation in the form and functionality of human
beings and animals, that gradually proceed over time. These changes are not due
to illness or random accidents or injuries. These transformations in the form and
viability of the human or animal body ultimately result in death.
Aging is a process that occurs over time and is gradual decline in the human and
animal body that lead to a decline in normal function and appearance. Aging is a
result of changes at the cellular level ( miotic, post miotic, and fibroplast cells
) along with bone structure and muscle tissue. These changes manifest themselves
with the ultimate decline in key organs ( liver, lungs, kidneys , and heart )Also
biological systems like the central nervous system, digestive , and reproduction
gradually decline leading to the ultimate death of humans and animals.
As follows are criteria for aging:
- Cumulative: Gradual signs of aging over time.
- Universal: The entire species show physical evidence of aging.
- Progressive: Aging occurs over an incremental period of time.
- Intrinsic: Aging will occur regardless of the environment humans or animals live
- Deleterious: Normal biological functions gradually deteriorate over time.
Disease like aging is defined as the decline or damage to the normal function of
the body. The aging process leads to ultimate biological decline. Diseases contribute
to the aging process and failures of organs and biological systems are often diagnosed
as a specific disease. Diseases associated with aging process, such as coronary
disease indicate that there is a correlation between aging and disease