Test cross - Mendelian genetics

Is there a way to distinguish the genotype of an organism expressing the dominant phenotype? The answer is YES! Mendel devised a method called test cross, where an organism of dominant phenotype but unknown genotype is crossed with a homozygous recessive individual. Case 1 If a purple-flowered plant (PP) is test-crossed to a white-flowered plant (pp), all...

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Mendel's postulates of inheritance - Mendelian genetics

Mendel's first three postulates of inheritance 1. Unit factors in pairs Genetics characters are controlled by unit factors that exist in pairs in an individual. If these factors appear in pairs, three combinations are possible: TT, Tt and tt. 2. Dominance / recessiveness When two unlike unit factors responsible for a single character are present in...

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Monohybrid inheritance - Mendelian genetics

A monohybrid cross is a cross that involved only one pair of contrasting traits. From Mendel's experiments, he noticed that: 1. If he crossed a true breed tall pea plant with a true breed dwarf pea plant, all offspring in F1 generation were tall. 2. If he intercrossed two tall pea plants from the first generation, some offspring in F2 generation were...

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Gregor Johann Mendel - Mendelian genetics

Gregor Johann Mendel (1822 - 1884) Johann Mendel, a monk in St. Thomas' monastery in Brno, Vienna, has a wide interests from religion to botany and mathematics. In 1866, he published the results of a series of experiments that laid the foundation of Genetics. In the following years and early 20th century, he established the concept of the gene as a...

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