Characteristic pattern of life changes that occur normally in humans, plants, and animals as they grow older. Some age changes begin at birth and continue until death; other changes begin at maturity and end at death.
The process, affecting organisms and most cells, whereby each cell division (mitosis) brings that cell (or organism composed of such cells) closer to its final cell division (i.e., death). Notable exceptions to this aging process include cancerous cells (e.g., myelomas) and the single-celled organism; both of which are “immortal.”
The process of growing old.
Characteristic pattern of life changes that occur normally in humans, plants, and animals as they grow older. Some age changes begin at birth and continue until death; other changes begin at maturity and end at death.
The processes involved from conception to death; an evolution of metabolic, endocrinological, and physiological change that occurs in the individual from inception through birth, childhood, adolescence, adulthood, and senescence. In the United States, the segment of the population over the age of 65 has grown rapidly.
Process of growing old. Generally during aging a person’s height decreases, bone tissue diminishes, hair becomes gray and/or is thinned or lost, nose and ears lengthen, eye lenses become more rigid, and other physical changes occur. The process seems to relate to an internal clock that is specific for each type of organism, the human maximum being about 105 years. Aging is believed to be influenced by genetics and lifestyle and possibly inhibited by exercise and mental activity, a positive attitude, and a balanced and restricted diet.
The decline, over time, of the body’s organ systems. Ear-ranging physiological changes are a part of aging. Homeostasis, the process through which the body adjusts to external change, becomes impaired. The reserve, or capacity, of many body functions is decreased. However, life expectancy in the United States nearly doubled in the 20th century. Today Americans who reach age 60 can expect to live beyond 80.
Growing older. Most authorities confine the term to the maturation and physiological changes in organ systems that occur after the 30th year of life.
Aging encompasses the natural physical and mental changes that occur over time and is associated with degenerative transformations in various organs and tissues. These changes include the loss of skin elasticity, progressive decline in organ function, cumulative damage to joints from wear and tear, and a decrease in muscle bulk and strength. The capacity for wound healing and resistance to infections also diminishes. Gradual loss of nerve cells can result in reduced sensory acuity and challenges with learning and memory. However, it is important to note that dementia, a cognitive impairment, only affects a minority of elderly individuals.
Heredity plays a significant role in determining life expectancy, yet various lifestyle factors can accelerate physical degeneration. Behaviors such as smoking, excessive alcohol consumption, poor dietary choices, and lack of physical exercise can hasten the decline of overall health. However, it is worth noting that advancements in medical science have led to a remarkable increase in life expectancy within developed nations over the past century. These advancements have contributed to improved healthcare, disease prevention, and enhanced treatment options, collectively resulting in longer and healthier lives for many individuals.