Asked by Anthony Cicero on May 06, 2024
Verified
Two parents with widow's peak and short fingers have a child with a continuous hairline and long fingers. What are the genotypes of the two parents? (W = widow's peak; S = short fingers)
A) WWSS × wwss
B) wwss × WWSS
C) WWss × WWss
D) WwSs × WwSs
E) WwSs × wwss
Widow's Peak
is a distinct V-shaped point in the hairline in the center of the forehead.
Genotypes
The genetic makeup of an organism, consisting of the alleles that an organism possesses.
Continuous Hairline
A hairline with an uninterrupted, smooth transition across the forehead, typically seen as an aesthetic feature.
- Apply the principles of Mendelian genetics to predict outcomes of monohybrid and dihybrid crosses.
- Calculate phenotypic and genotypic ratios in offspring resulting from different types of genetic crosses.
Verified Answer
RW
rwererwerwe werwerwrwerMay 07, 2024
Final Answer :
D
Explanation :
- Widow's peak is dominant, so one parent must be heterozygous for the trait and the other parent can either be homozygous recessive or heterozygous. Therefore, the possible genotypes for the parents are: WwSs or WWss.
- Short fingers is also dominant, so one parent must be heterozygous for the trait and the other parent can either be homozygous recessive or heterozygous. Therefore, the possible genotypes for the parents are: WwSs or wwSs.
- The child has a continuous hairline and long fingers, which are both recessive traits. This means that the child must be homozygous recessive for both traits (wwss).
- Combining the possible genotypes of the parents (WwSs and WWss for widow's peak, and WwSs and wwSs for short fingers), the only option that can result in a homozygous recessive child is D: WwSs × WwSs.
- Short fingers is also dominant, so one parent must be heterozygous for the trait and the other parent can either be homozygous recessive or heterozygous. Therefore, the possible genotypes for the parents are: WwSs or wwSs.
- The child has a continuous hairline and long fingers, which are both recessive traits. This means that the child must be homozygous recessive for both traits (wwss).
- Combining the possible genotypes of the parents (WwSs and WWss for widow's peak, and WwSs and wwSs for short fingers), the only option that can result in a homozygous recessive child is D: WwSs × WwSs.
Learning Objectives
- Apply the principles of Mendelian genetics to predict outcomes of monohybrid and dihybrid crosses.
- Calculate phenotypic and genotypic ratios in offspring resulting from different types of genetic crosses.