GENETICS THEORIES Aristotle and Charles Darwin's Theory of Pangenesis In 1868 in England, Charles Darwin proposed his pangenesis theory to describe the units of inheritance between parents and offspring and the processes by which those units control development in offspring. Darwin coined the concept of gemmules, which he said referred to hypothesized minute particles of inheritance thrown off by all cells of the body. Pangenesis theory originated from the claim that characteristics acquired during an organism's life were heritable. A theory of inheritance of acquired characteristics (IAC) had persistent for almost two thousand years, since Greek antiquity. In 1868, Darwin proposed the pangenesis theory in the concluding chapter of his book The Variation of Animals and Plants under Domestication. In Darwin's account, the theory of pangenesis complemented his theory of natural selection, described in his 1859 On the Origin of Species by Means of Natural Selection. Darwin proposed pangenesis theory to complement his 1859 theory of evolution via natural selection. Darwin coined the term pangenesis, with "pan-" meaning whole, and "genesis" indicating origin. With the term pangenesis, Darwin suggested that all parts of the parents could contribute to the evolution and development of the offspring. Importance and connect theory in genetics Jean-Baptiste Lamarck - inheritance of acquired characters. Scientists are not always remembered for the ideas they cherished most. In the case of the French biologist Jean-Baptiste Lamarck, his name since the end of the nineteenth century has been tightly linked to the idea of the inheritance of acquired characters. This was indeed an idea that he endorsed, but he did not claim it as his own nor did he give it much thought. He took pride instead in advancing the ideas that (1) nature produced successively all the different forms of life on earth, and (2) environmentally induced behavioral changes lead the way in species change. This article surveys Lamarck’s ideas about organic change, identifies several ironies with respect to how his name is commonly remembered, and suggests that some historical justice might be done by using the adjective “Lamarckian” to denote something more (or other) than a belief in the inheritance of acquired characters. August Weismann's Theory of the Germ-Plasm **Blending Theory, Greek and Romans **Chromosome inheretance PH morgan?? **OG Gregor mendal theory