Biological immortality can be defined as the absence of a sustained increase in rate of mortality as a function of chronological age. A cell or organism that does not experience, or at some future point will cease, aging is biologically immortal. Biology is the branch of science dealing with the study of life. ... In biology, senescence is the state or process of aging which follows the period of development. ...

There is no organism or individual cell that is literally immortal. Any "immortal" cell or organism can be killed by physical destruction. In biology and ecology, an organism (in Greek organon = instrument) is a complex adaptive system of organs that influence each other in such a way that they function as a more or less stable whole and have properties of life. ... Cells in culture, stained for keratin (red) and DNA (green) The cell is the structural and functional unit of all living organisms, and are sometimes called the building blocks of life. ... Immortality (or eternal life) is the concept of existing for a potentially infinite, or indeterminate length, of time. ...

Biologists have chosen the word immortal to designate cells that do not undergo cellular senescence (the state wherein cells no longer divide because of DNA damage or shortened telomeres). The term immortalization was first applied to cancer cells that developed the telomere-lengthening enzyme telomerase, and thereby avoided cellular senescence. A biologist is a scientist devoted to and producing results in biology through the study of organisms. ... Cells in culture, stained for keratin (red) and DNA (green) The cell is the structural and functional unit of all living organisms, and are sometimes called the building blocks of life. ... The Hayflick limit was discovered by Leonard Hayflick in 1965. ... DNA damage resulting in multiple broken chromosomes DNA repair is a process constantly operating in cells; it is essential to survival because it protects the genome from damage and harmful mutations. ... A telomere is a region of highly repetitive DNA at the end of a chromosome that functions as a disposable buffer. ... When normal cells are damaged beyond repair, they are eliminated by apoptosis. ... A telomere is a region of highly repetitive DNA at the end of a chromosome that functions as a disposable buffer. ... Ribbon diagram of the catalytically perfect enzyme TIM. An enzyme is a protein that catalyzes, or speeds up, a chemical reaction. ... Telomerase is an enzyme, discovered by Elizabeth Helen Blackburn and Carol Greider, that adds specific DNA sequence repeats, (TTAGGG in all vertebrates) to the 3 (three prime) end of DNA strands, in the telomere regions at the ends of chromosomes which contain condensed DNA material during replication. ...

Bacteria can be said to be biologically immortal, but only as a species. An individual bacterium can easily die. The two daughter bacteria resulting from cell division of a parent bacterium can be regarded as unique individuals or as members of a biologically "immortal" species. The two daughter cells can be regarded as "rejuvenated" copies of the parent cell because damaged macromolecules have been split between the two cells and diluted. This is the exact same sense in which stem cells and gametes can be regarded as "immortal". Similarly, Hydra, lobsters and a number of other species are regarded as never aging because they are composed entirely of cells that never cease dividing (and diluting damaged molecules). Subgroups Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular: bacterium) are a major group of living organisms. ... Cell division is the process by which a cell (called the parent cell) divides into two cells (called daughter cells). ... Biology is the branch of science dealing with the study of life. ... Rejuvenation is the procedure of reversing the aging process, thus regaining youth. ... A macromolecule is a molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetition of units derived, actually or conceptually, from molecules of low relative molecular mass. ... Mouse embryonic stem cells. ... Gametes (in Greek: γαμέτες) —also known as sex cells, or spores—are the specialized germ cells that come together during fertilization (conception) in organisms that reproduce sexually. ... Species Hydra americana Hydra attenuata Hydra canadensis Hydra carnea Hydra cauliculata Hydra circumcincta Hydra hymanae Hydra littoralis Hydra magnipapillata Hydra minima Hydra oligactis Hydra oregona Hydra pseudoligactis Hydra rutgerensis Hydra utahensis Hydra viridis Hydra is the genus name of a simple, fresh-water animal possessing radial symmetry. ... Subfamilies and Genera Neophoberinae Acanthacaris Thymopinae Nephropsis Nephropides Thymops Thymopsis Nephropinae Homarus Nephrops Homarinus Metanephrops Eunephrops Thymopides Clawed lobsters comprise a family (Nephropidae, sometimes also Homaridae) of large marine crustaceans. ... Ageing or aging is the process of getting older. ...

Some life extensionists have the hope that humans may someday become biologically immortal. This would obviously not be the same as being literally immortal because people can always be murdered or die in accidents. Many people practice cryonics with the expectation that humans will someday achieve biological immortality. Notable books by cryonicists along this line are The First Immortal by James L. Halperin, The Prospect of Immortality by Robert Ettinger and Forever For All by Dr. R. Michael Perry. Such views have been bolstered by the promise of nanotechnology, and specifically of nanomedicine. A study published in Physiological and Biochemical Zoology in 2005 indicates that biological immortality may exist in humans at a late stage in life: "the exponential increase in age-specific death rate seemed to slow down considerably, if not cease." [1] Life extension refers to an increase in maximum lifespan or average lifespan, especially in mammals. ... Immortality (or eternal life) is the concept of existing for a potentially infinite, or indeterminate length, of time. ... This bigfoot Dewar flask is custom-designed to contain four wholebody patients and six neuropatients immersed in liquid nitrogen at -196 degrees Celsius. ... This bigfoot Dewar flask is custom-designed to contain four wholebody patients and six neuropatients immersed in liquid nitrogen at -196 degrees Celsius. ... James L. Halperin, born October 31, 1952 in Boston, Massachusetts, is an American author and businessman. ... Robert Chester Wilson Ettinger (born December 4, 1918) is known as the father of cryonics due to the impact of his 1962 book THE PROSPECT OF IMMORTALITY. He founded the Cryonics Institute and the related Immortalist Society and until 2003 served as their President. ... A mite next to a gear set produced using MEMS, the precursor to nanotechnology. ... Nanomedicine is the medical application of nanotechnology and related research. ...

Another ambitious project for achieving biological immortality in humans and mammals is that of biogerontologist Aubrey de Grey of Cambridge University. Dr. de Grey proposes that damage to macromolecules, cells, tissues and organs can be repaired by advanced biotechnology. He calls his project SENS (Strategies for Engineered Negligible Senescence). Dr. de Grey has created a Methuselah Mouse Prize which awards money to researchers who can extend the lifespan of, or rejuvenate mice. Gerontology is the study of the elderly, and of the aging process itself. ... Aubrey de Grey Aubrey de Grey (D.O.B April 20, 1963) is a biomedical gerontologist and bioinformatician at the Department of Genetics, University of Cambridge, England. ... The University of Cambridge is the second-oldest university in the English-speaking world, with one of the most selective sets of entry requirements in the United Kingdom. ... A macromolecule is a molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetition of units derived, actually or conceptually, from molecules of low relative molecular mass. ... Cells in culture, stained for keratin (red) and DNA (green) The cell is the structural and functional unit of all living organisms, and are sometimes called the building blocks of life. ... Biological tissue is a substance made up of cells that perform a similar function. ... In biology, an organ (Latin: organum, instrument, tool) is a group of tissues, which perform a specific function or group of functions. ... Biotechnology is a technology based on biology, especially when used in agriculture, food science, and medicine. ... Aubrey de Grey is Editor-in-Chief of the Rejuvenation Research journal, which deals with topics related to engineered negligible senescence. ... Aubrey de Grey is Editor-in-Chief of the Rejuvenation Research journal, which deals with topics related to engineered negligible senescence. ... The Methuselah Mouse Prize is a growing $3 million prize started in 2003 to accelerate research into slowing and eventually reversing cellular aging and breakdown in humans. ... Rejuvenation is the procedure of reversing the aging process, thus regaining youth. ...

See also

• Engineered negligible senescence
• Immortality Institute
• Life extension
• Maximum lifespan
• Methuselah Mouse Prize

Aubrey de Grey is Editor-in-Chief of the Rejuvenation Research journal, which deals with topics related to engineered negligible senescence. ... The Immortality Institute (ImmInst) is a 501(c)(3) nonprofit organization with more than 1,500 members which works to fulfill its goal to conquer the blight of involuntary death. ... Life extension refers to an increase in maximum lifespan or average lifespan, especially in mammals. ... Maximum life span is a measure of the maximum number of years a member of a group can be expected to survive. ... The Methuselah Mouse Prize is a growing $3 million prize started in 2003 to accelerate research into slowing and eventually reversing cellular aging and breakdown in humans. ...

External links

• Biological Immortality encyclopedic entry from Principia Cybernetica
• Late Life: A New Frontier for Physiology study indicates biological immortality in humans late in life
• Cellular Senscence and Apoptosis in Aging
• senescence.info Informational website related to aging research and immortality.
• The First Immortal: free download
• The Prospect of Immortality: free download
• Geron Announces Launch of Telomerase-Immortalized Cell Line Geron Corporation