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FUNCTION OF EARLY DEATH. "In many semelparous organisms, the adaptive function of the nominal ‘death program’ is apparently to increase reproduction, with organismal death resulting as an incidental side-effect (making organismal senescence an example of “by-product death”." https://lnkd.in/ecP3KMX View in LinkedIn

“THE ENIGMA that is the Cambrian Explosion is one of the most perplexing, fascinating, and important events in the evolution of life on Earth. Enigmatic due to the lack of evidence, and that which we do have is not necessarily clear in its implications producing an array of varying views, and hypotheses.” https://lnkd.in/ex6BW5w View in LinkedIn

SOMETIMES PROGRAMMED. "There is substantial evidence for genetic control of senescence in some iteroparous animals, indicating that senescence is at least sometimes “programmed” (in the inclusive sense) and highlighting the question of the relationship between aging “programs” and selection." https://lnkd.in/ecP3KMX View in LinkedIn

PREFERENTIAL SURVIVAL. "Natural selection is the differential reproduction of genotypes. ‘Natural selection […] is the differential and non-random reproduction of different alternative alleles in a population’...population genetics and modern evolutionary theory equate natural selection with differential reproduction of alternative forms of genes, genotypes, or other reproducible units’." Lovely definition. https://lnkd.in/eS_4y_J View in LinkedIn

"WHY A HIGHER MUTATION RATE occurs in the mitochondria in contrast to the nucleus appears related to the generation of genetic diversity useful in exploiting new ecological niches. In particular, the enzymes involved in energy generation by the mitochondrion. The mitochondrion is the powerhouse of the cell." https://lnkd.in/e533NK2 View in LinkedIn

"WHY A HIGHER MUTATION RATE occurs in the mitochondria in contrast to the nucleus appears related to the generation of genetic diversity useful in exploiting new ecological niches. In particular, the enzymes involved in energy generation by the mitochondrion. The mitochondrion is the powerhouse of the cell." https://lnkd.in/e533NK2 View in LinkedIn

MITOCHONDRIAL INHERITANCE. The maternal inheritance of mitochondrial DNA, a primer. https://lnkd.in/eUuXV43 View in LinkedIn

HOMOPLASTY VS HETROPLASTY. “A mammalian cell has a single nucleus which contains a single genome. The genomic DNA is identical across all cells in an organism. A mammalian cell has many mitochondria and every mitochondria has its own (circular) genome. All the many individual copies of mtDNA exist independently of each other. If all the mtDNA in a cell are identical, then they are homoplasmic. (Common, "normal" situation). If one (or more) of the mtDNA in a single cell acquires a mutation, then the cell will have a mix of mutant-mtDNA and WT-mtDNA. These cells are now heteroplasmic.” https://lnkd.in/eeWUxj8 View in LinkedIn

"EXTRANUCLEAR INHERITANCE or cytoplasmic inheritance is the transmission of genes that occur outside the nucleus. It is found in most eukaryotes and is commonly known to occur in cytoplasmic organelles such as mitochondria and chloroplasts or from cellular parasites like viruses or bacteria." This breaks all of Mendel’s famous genetic laws. https://lnkd.in/eWiwdUk View in LinkedIn

"HETEROPLASMY is the presence of more than one type of organellar genome (mitochondrial DNA or plastid DNA) within a cell or individual. It is an important factor in considering the severity of mitochondrial diseases. Because most eukaryotic cells contain many hundreds of mitochondria with hundreds of copies of mitochondrial DNA, it is common for mutations to affect only some mitochondria, leaving most unaffected." https://lnkd.in/eHYuPyQ View in LinkedIn