1. Senescence typically refers to a cellular process, commonly known as cell senescence, while aging, ageing, and aged are terms that are often used interchangeably to describe the deterioration of the whole body.
2. Cell senescence refers to a state where cells permanently exit the cell division cycle but still retain some functional capabilities. In contrast, aging refers to the progressive decline in tissue structure and organ function over time.
3. It is important to note that the senescence of individual cells does not necessarily equate to the aging of the entire organism. For instance, a young person with a few white hairs would not be considered elderly.
4. However, as the number of senescent cells within the body increases, it gradually contributes to the overall aging of the organism.
