Question

Test cross involves-

• A. Crossing between two genotypes with recessive trait
• B. Crossing between two F${}_1$ hybrids
• C. Crossing the F${}_1$ hybrid with a double recessive genotype
• D. Crossing between two genotypes with dominant trait

Answer 1

Answer: (C)

Crossing the F${}_1$ hybrid with a double recessive genotype

• The test cross involves the crossing of F1 hybrid with a double recessive genotypic parent.
• By test cross, the heterozygocity and homozygocity of the organism can be tested.
  
• Thus, the offspring will be 100% dominant, if the individual which crossed with recessive parent i.e., (tt) was homozygous dominant and ratio will be 50% dominant and 50% recessive so that proves individual was heterozygous dominant. so , answer is option C .