In 1865,Austrian scientists Gregor Mendel published a paper entitled Experiments on Plant Hybrids,and put forward two laws:Principles of Independent Segregation and Independent Assortment; Figure 1.1 Gregor Mendel.(Source:Courtesy of Dept.of Lbrany Services/American Museum of Natural History.Neg.no.219467.)
In 1865, Austrian scientists Gregor Mendel published a paper entitled Experiments on Plant Hybrids, and put forward two laws: Principles of Independent Segregation and Independent Assortment;
parental generation parental generation RR gametes R A gametes hybrid F generation F:generation Rr female male gametes R R r gametes A gametes R R F2 generation a A female male gametes gametes RR A a Rr F2 generation 1-1 1-2 How Mendel's first law(independent segregation) explains the 3:1 ratio of dominant to recessive The inheritance of flower color in the phenotypes among the F2 progeny snapdragon
How Mendel’s first law (independent segregation) explains the 3:1 ratio of dominant to recessive phenotypes among the F2 progeny The inheritance of flower color in the snapdragon
parental generation X RRYY myy y gametes y F,generation 0 RrYy RY R gametes F2generation RY RY gametes Ry RRYY Ry gametes RRYy RRYy RRyy RrYY RrYy RrYy RrYy RrYy Rryy YY Rryy mYy How Mendel's second myy law (independent 1-3 assortment)operates?
How Mendel’s second law (independent assortment) operates?
In 1900,Hugo de Vries,Carl Correns,Erich von Tschermak rediscovered Mendelian inheritance law. In19o9,丹麦geneticists W.Johannsen dubbed “Gene”to substitute Mendel's genetic unit. By the end of 1900,chromosome theory of inheritance was put forwarded. In 1910,American scientists Thomas H.Morgan confirmed gene is located on chromosome and discovered genetic recombination phenomenon
In 1900, Hugo de Vries, Carl Correns, Erich von Tschermak rediscovered Mendelian inheritance law. In 1909, 丹麦geneticists W. Johannsen dubbed “Gene” to substitute Mendel’s genetic unit. By the end of 1900, chromosome theory of inheritance was put forwarded. In 1910, American scientists Thomas H. Morgan confirmed gene is located on chromosome and discovered genetic recombination phenomenon
a parental generation parental generation red phenotype white white♀phenotype red genotype genotype gametes gametes F:gene F:generation red red white d F2 generation red♀rod♀red white red white red white Thomas Hunt Morgan WY WY The inheritance of a sex-linked gene in Drosophila
Thomas Hunt Morgan The inheritance of a sex-linked gene in Drosophila