Symbiogenesis, or endosymbiotic theory, is an evolutionary theory that explains the origin of eukaryotic cells from prokaryotes.It states that several key organelles of eukaryotes originated as a symbiosis between separate single-celled organisms.he theory of symbiogenesis (Greek: ÏÏÎ½ syn together, Î²Î¯ÏÏÎ¹Ï biosis living, and Î³Î­Î½ÎµÏÎ¹Ï genesis origin or birth) theory were first articulated by the Russian botanist Konstantin Mereschowsky in 1910, although he described the fundamental elements of the theory were described in a paper five years earlier.
Definition of rider: Additional clause, document, or slip of paper that adds, alters, amends, or removes the provisions of an associated or attached agreement or contract (such as an insurance policy) or a negotiable ...
Cavalry is a unit of soldiers mounted on horseback. As stated above, the word Cavalry comes from the French word cavalerie, or chevalerie and the Latin word caballus, meaning horse. Horseback riding probably evolved independently in the Eurasian steppes and the mountains above the Mesopotamian plain.