how was it discovered initially?
The existence of discrete inheritable units was first suggested by Gregor Mendel, he studied inheritance patterns in 8000 common edible pea plants.
Gene
The existence of discrete inheritable units was first suggested by Gregor Mendel (1822–1884). From 1857 to 1864, in Brno, Austrian Empire (today's Czech Republic), he studied inheritance patterns in 8000 common edible pea plants, tracking distinct traits from parent to offspring. He described these mathematically as 2 combinations where n is the number of differing characteristics in the original peas. Although he did not use the term "gene", he explained his results in terms of discrete inherited units that give rise to observable physical characteristics. This description prefigured Wilhelm Johannsen's distinction between genotype (the genetic material of an organism) and phenotype (the observable traits of that organism). Mendel was also the first to demonstrate independent assortment, the distinction between dominant and recessive traits, the distinction between a heterozygote and homozygote, and the phenomenon of discontinuous inheritance.
what is meant by the term single gene trait A single gene encode slightly different versions of a protein, which cause different phenotypical traits. what is a gene? It is a sequence of nucleotides in DNA or RNA that encodes the synthesis of a gene product, either RNA or protein.
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Gene [SEP] Discovery of discrete inherited units
The existence of discrete inheritable units was first suggested by Gregor Mendel (1822–1884). From 1857 to 1864, in Brno, Austrian Empire (today's Czech Republic), he studied inheritance patterns in 8000 common edible pea plants, tracking distinct traits from parent to offspring. He described these mathematically as 2 combinations where n is the number of differing characteristics in the original peas. Although he did not use the term "gene", he explained his results in terms of discrete inherited units that give rise to observable physical characteristics. This description prefigured Wilhelm Johannsen's distinction between genotype (the genetic material of an organism) and phenotype (the observable traits of that organism).