If 75% of the offsprings show dominant character, the parents are ___.
If 75% of the offsprings show dominant character, the parents are
The correct option is A Both heterozygous
If both parents are heterozygous, then there is a 75% chance that the offsprings show dominant character. Let us assume that both parents are heterozygous for the gene 'T'. That means both are of the genotype Tt. Each parent thus produces two types of gametes, one carrying the dominant allele T and the other having the recessive allele t. So, the genotypes of the F1 would be TT, Tt and tt. A total of four progenies are produced, out of which one will be homozygous dominant (TT), two will be heterozygous dominant (Tt) and one will be homozygous recessive (tt). So, the dominant character is seen in 3 out of the total four progeny, which is 75% of the progeny. If one parent is homozygous dominant and another homozygous recessive, all progeny will be heterozygous.
If both parents are heterozygous, then there is a 75% chance that the offsprings show dominant character. Let us assume that both parents are heterozygous for the gene 'T'. That means both are of the genotype Tt. Each parent thus produces two types of gametes, one carrying the dominant allele T and the other having the recessive allele t. So, the genotypes of the F1 would be TT, Tt and tt. A total of four progenies are produced, out of which one will be homozygous dominant (TT), two will be heterozygous dominant (Tt) and one will be homozygous recessive (tt). So, the dominant character is seen in 3 out of the total four progeny, which is 75% of the progeny. If one parent is homozygous dominant and another homozygous recessive, all progeny will be heterozygous.
