Question

If two lizard-footed people had children and 75% of the offspring had lizard feet and

25% had normal feet what are the genotypes of the two lizard-footed people?

Answer 1

Ll

Step-by-step explanation:

If lizard feet trait is governed by one gene, let it be represented by L.

Since the offspring showed the trait in 3 : 1 ratio ( 75% lizard-footed and 25% normal-footed), it follows the Mendelian laws of inheritance. According to it, a monohybrid cross gives 3 : 1 ratio in F2 generation. This is possible when both the parents are heterozygous. Here,

If parents are heterozygous lizard-footed (Ll):

L l

L LL Ll

l Ll ll

75% of offspring will have lizard feet since they have at least one dominant L allele. 25% of offspring will have normal feet because they have only recessive alleles (ll). Hence, it can be stated that genotype of both the lizard-footed parents is Ll.