Answer:
Percentage of offspring with straight hair: 75%
Percentage of offspring with curly hair: 25%
Genotypic ratio: 1:2:1
Step-by-step explanation:
In a monohybrid cross between two parents heterozygous (carrying one dominant and one recessive allele) for straight hair, where straight hair is dominant (S) and curly hair is recessive (s), the genotypes of the parents can be represented as Ss.
To determine the percentage of their offspring with straight hair and curly hair, we can use Punnett square analysis.
The Punnett square for the monohybrid cross between the parents would look like this:
S s
S SS Ss
s Ss ss
From the Punnett square, we can see that there are four possible genotypes for the offspring: SS, Ss, Ss, and ss.
The genotypes SS and Ss correspond to individuals with straight hair, while ss corresponds to individuals with curly hair.
So, the percentage of their offspring with straight hair would be 75% (3 out of 4 possible genotypes), and the percentage with curly hair would be 25% (1 out of 4 possible genotypes).
The genotypic ratio for their offspring would be 1:2:1, meaning that for every four offspring, one would have the genotype SS (homozygous dominant for straight hair), two would have the genotype Ss (heterozygous for straight hair), and one would have the genotype ss (homozygous recessive for curly hair).
Hope this helps!