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"GERM CELLS are highly specialized cells that form gametes, and they are the only cells within an organism that contribute genes to offspring. Germline stem cells (GSCs) sustain gamete production, both oogenesis (egg production) and spermatogenesis (sperm production), in many organisms." https://lnkd.in/dsBeTUt View in LinkedIn

GENERATING UNIQUENESS. “Meiosis, from the Greek word meioun, meaning "to make small," refers to the specialized process by which germ cells divide to produce gametes. Because the chromosome number of a species remains the same from one generation to the next, the chromosome number of germ cells must be reduced by half during meiosis. To accomplish this feat, meiosis, unlike mitosis, involves a single round of DNA replication followed by two rounds of cell division. Meiosis also differs from mitosis in that it involves a process known as recombination, during which chromosomes exchange segments with one another. As a result, the gametes produced during meiosis are genetically unique.” https://lnkd.in/dBpemgQ View in LinkedIn

ANEUPLOIDY. "Errors in the transmission of chromosomes during either meiosis or mitosis can lead to aneuploidy; that is, an aberrant number of chromosomes." http://www.sciencedirect.com/science/article/pii/S0092867403000837 View in LinkedIn

SO ENDS this curated dip into biological resource allocation. While Darwinian competition for limited resources has been documented at the ecological, population, cellular and intracellular level, it comes as no surprise that it exists at molecular levels also. The triumph of the fittest at each level must have different drivers. At the molecular level it must be reaction kinetics based on molecular shapes, while at population levels it is about successfully generating viable offspring. At what point competition and cooperation overlap is the interesting question. View in LinkedIn

TWO CELL DIVISION TYPES. "Mitosis and meiosis are two different types of cell division cycles with entirely different outcomes with definite biological implication for almost all eukaryotic species." https://lnkd.in/d8cXuPE View in LinkedIn

CHEMICAL DARWINIAN COMPETITION. “In recent years, an extension of the Darwinian framework is being considered for the study of prebiotic chemical evolution, shifting the attention from homogeneous populations of naked molecular species to populations of heterogeneous, compartmentalized and functionally integrated assemblies of molecules.” https://lnkd.in/d-UDSAh View in LinkedIn

CONSERVED PLOIDY. "Precise and timely segregation of genetic material and conservation of ploidy are the two foremost requirements for survival of a eukaryotic organism. Two highly regulated cell division processes, namely mitosis and meiosis are central to achieve this objective. The modes of chromosome segregation are distinct in these two processes that generate progeny cells of equal ploidy and half the ploidy in mitosis and meiosis, respectively." https://lnkd.in/d8cXuPE View in LinkedIn

SECOND MAJOR FORCE. "Repression of competition within groups joins kin selection as the second major force in the history of life shaping the evolution of cooperation. When opportunities for competition against neighbors are limited within groups, individuals can increase their own success only by enhancing the efficiency and productivity of their group." https://lnkd.in/duWA75V View in LinkedIn

HALVING IS HARD. "The behavior of chromosomes in meiosis is much more complex than in mitosis. Additional demands such as chiasmata formation, mono-orientation of sister kinetochores, protection of centromeric cohesion, and prevention of DNA replication between the two divisions are imposed upon the chromosome segregation machinery." http://www.sciencedirect.com/science/article/pii/S0092867403000837 View in LinkedIn

SELFISH BRAIN. "The presented model includes a newly discovered ‘principle of balance’ of how pairs of high and low-affinity receptors can originate setpoints in biological systems. In this ‘Selfish Brain Theory’, the neocortex and limbic system play a central role in the pathogenesis of diseases such as anorexia nervosa and obesity." http://www.sciencedirect.com/science/article/pii/S0149763404000259 View in LinkedIn