Term : Gene
Origin: Anc Greek γενεά/ genea(=generation) < γεννώ/geno (=birth to)
Coined: Although the notion of a gene was began with Gregor Mendel’s work on pea plants (1866), the term gene was coined by Wilhelm Johannsen (1857 - 1927), a Danish botanist and geneticist, in his translated to German book “ Elemente der exakten Erblichkeitslehre.” In this book Johannsen in 1909 used the term “gene” in order to describe the fundamental physical and functional units of heredity. This term was coined to describe Mendel's factors of inheritance and it was in opposition to the then common pangene that stemmed from Darwin's theory of pangenesis*. In the 1940s and early 1950s, experiments pointed to DNA as the portion of chromosomes that held genes.
*Pangenesis : Charles Darwin’s hypothetical mechanism for hereditary. Aaccording this theory of 1868, gemmules containing hereditary information from every part of the body throws off into the blood and finally they are collected in the reproductive cells in gonads as the units of hereditary transmission. Twenty years later in 1889, De Vries, a Dutch botanist, published his book "Intracellular Pangenesis" in which, based on a modified version of Darwin’s theory, he postulated that different characters have different hereditary carriers and that inheritance of specific traits in organisms comes in particles. He called these units pangenes, a term 20 years later to be shortened to genes by Wilhem Johannsen.
The etymology of the word pangenesesis comes from the Greek word παν/pan(=whole) γένεσις/genesis (=birth, origin)
Definition
A hereditary unit consisting of a sequence of DNA that occupies a specific location on a chromosome and usually that encodes a specific protein responsible for a particular characteristic in an organism.
Runon derivatives :
Genetics, genomics, genus, genotype
comments:
In 1905 Wilhelm Johannsen coined the terms genotype to describe the genetic constitution of an individual, and phenotype, to describe the visible result of the interaction between genotype and environment.
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