fall into two main categories, programmed and damage-related.Programmed factors follow a biological timetable, perhaps one that might be a continuation of the one that regulates childhood growth and development.Once these factors are accounted for, the optimal body weight above age 65 corresponds to a leaner body mass index of 23 to 27.
fall into two main categories, programmed and damage-related.Programmed factors follow a biological timetable, perhaps one that might be a continuation of the one that regulates childhood growth and development.Once these factors are accounted for, the optimal body weight above age 65 corresponds to a leaner body mass index of 23 to 27.Tags: Professional Dissertation Help ReviewsSample Research Proposal AbstractScience And Technology English EssayName 4 Essays By Thomas PaineBusiness Plan Pro ReviewsThe Deer At Providencia Essay
Ageing is among the greatest known risk factors for most human diseases: of the roughly 150,000 people who die each day across the globe, about two thirds die from age-related causes.
The causes of ageing are uncertain; current theories are assigned to the damage concept, whereby the accumulation of damage (such as DNA oxidation) may cause biological systems to fail, or to the programmed ageing concept, whereby internal processes (such as DNA methylation) may cause ageing.
Programmed ageing should not be confused with programmed cell death (apoptosis).
In 1934, it was discovered that calorie restriction can extend lifespan by 50% in rats and this has motivated research into delaying and preventing ageing.
Older adults, however, may not suffer depression as much as younger adults, and were paradoxically found to have improved mood despite declining physical health.
A distinction can be made between "proximal ageing" (age-based effects that come about because of factors in the recent past) and "distal ageing" (age-based differences that can be traced to a cause in a person's early life, such as childhood poliomyelitis).Individual variations in rate of cognitive decline may therefore be explained in terms of people having different lengths of life.which can lead to isolation and possible depression.To submit proposals to either launch new journals or bring an existing journal to MIT Press, please contact Director for Journals and Open Access, Nick Lindsay at [email protected] To submit an article please follow the submission guidelines for the appropriate journal(s).Ageing or aging (see spelling differences) is the process of becoming older.The term refers especially to human beings, many animals, and fungi, whereas for example bacteria, perennial plants and some simple animals are potentially biologically immortal.In the broader sense, ageing can refer to single cells within an organism which have ceased dividing (cellular senescence) or to the population of a species (population ageing).coli may split into distinguishable daughter cells, which opens the theoretical possibility of "age classes" among bacteria.Even within humans and other mortal species, there are cells with the potential for immortality: cancer cells which have lost the ability to die when maintained in a cell culture such as the He La cell line, The spectrum ranges from mild cognitive impairment to the neurodegenerative diseases of Alzheimer's disease, cerebrovascular disease, Parkinson's disease and Lou Gehrig's disease.In contrast, many species can be considered immortal: for example, bacteria fission to produce daughter cells, strawberry plants grow runners to produce clones of themselves, and animals in the genus Hydra have a regenerative ability by which they avoid dying of old age.Early life forms on Earth, starting at least 3.7 billion years ago, which occurred with the emergence of the fungal/animal kingdoms approximately a billion years ago, and the evolution of seed-producing plants 320 million years ago.