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Principles of Inheritance and Variation — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYPrinciples of Inheritance and Variation3 Marks
Question
Define and design a test-cross###Explain the test cross by example.
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Answer

When organism of F perp generation is crossed with its recessive parent, it is called Test cross. This cross produced offsprings of which 50% are homozygous recessive and 50% are heterozygous dominant e.g. If hybrid red flowered plant of F1 generation is crossed with recessive white flowered parentit yields red and white flowered plants in 1:1 ratio i.e. phenotypic and genotypic ratio so obtained is same.
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