It is said that Mendel proposed that the factor controlling any character is discrete and independent. This proposition was based on the
observations that the offspring of a cross made between the plants having two contrasting characters shows only one character without any blending
self-pollination of $F_1$ offsprings
cross-pollination of $F_1$-generation with recessive parent
Two genes ' $A$ ' and ' $B$ ' are linked. In a dihybrid cross involving these two genes, the $F_1$ heterozygote is crossed with homozygous recessive parental type (aa bb ). What would be the ratio of offspring in the next generation?
$1: 1: 1: 1$
$9: 3: 3: 1$
$3: 1$
$1: 1$
In the $F_2$-generation of a Mendelian dihybrid cross the number of phenotypes and genotypes are
phenotypes-4, genotypes-16
phenotypes-9, genotypes-4
phenotypes-4, genotypes-8
phenotypes-4, genotypes-9
Mother and father of a person with ' 0 ' blood group have ' $A$ ' and ' $B$ ' blood group respectively. What would be the genotype of both mother and father?
Mother is homozygous for ' A ' blood group and father is heterozygous for ' B '
Mother is heterozygous for ' A ' blood group and father is homozygous for ' B '
Both mother and father are heterozygous for ' A ' and ' B ' blood group respectively
Both mother and father are homozygous for ' A ' and ' B ' blood group respectively
What is the cross between the progeny of $F_1$ and the homozygous recessive parent called? How is it useful?
When a progeny of $F_1$ is crossed with the homozygous recessive parent, it is called test cross.
Test cross between pure dominant $(\mathrm{A})$ and hybrid dominant $(\mathrm{B})$ individuals with recessive parent is shown below
Such a cross is useful to determine the genotype of an unknown trait, i.e., whether it is heterozygous or homozygous dominant for the trait.