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प्रश्न
Define the following:
Test cross
Define a test-cross.
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उत्तर १
Test cross is a cross between an organism with an unknown genotype and a recessive parent. It is used to determine whether the individual is homozygous or heterozygous for a trait.
उत्तर २
Crossing of an F1 individual having a dominant phenotype with its homozygous recessive parent is called a test cross. A test cross is performed to determine the genotype of the F2 plant. In a typical test, a cross, an organism showing a dominant phenotype and whose genotype is to be determined is crossed with one that is homozygous recessive for the allele being investigated, instead of self-crossing.
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संबंधित प्रश्न
Name the ‘two’ types of maps generated by H.G.P.
How many linkage groups are present in Drosophila melanogaster?
Which of the following statement/s are INCORRECT with respect to crossing over?
i. Crossing over produces recombinations of genes by interchanging and exchanging corresponding segments between nonsister chromatids of homologous chromosomes.
ii. Crossing over occurs during zygotene of prophase I of meiosis.
Analyze the following statements and select the correct option.
- Due to incomplete linkage, the parental traits are inherited in offsprings.
- Due to incomplete linkage, new traits occur in offsprings.
- X chromosome of Drosophila males show complete linkage.
- In Zea mays - colour and shape of grain show complete linkage
Two dominant non-allelic genes are 50 map units apart. The linkage is ______.
Two crosses between the same pair of genotypes or phenotypes in which the sources of the gametes are reversed in one cross, is known as ______.
Mr. Kapoor has Bb autosomal gene pair and d allele sex-linked. What shall be proportion of Bd in sperms?
What will be the distribution of phenotypic features in the first filial generation after a cross between a homozygous female and a heterozygous male for a single locus?
What is true about the crossing over between linked genes?
T. H. Morgan used ______ for his experiments in linkage.
