Which diagram shows the possible gene combinations from a genetic cross?

Which diagram shows the possible gene combinations from a genetic cross?

• A. Pedigree chart
• B. Karyotype
• C. Gel electrophoresis
• D. Punnett square

Answer: (D)

Predicting offspring genotypes from parental alleles is best shown with a Punnett square. This diagram lays out the allele combinations that can appear in the next generation by placing one parent’s gametes along the top and the other parent’s gametes along the side, then filling each intersection with the resulting allele pair. It visually displays all possible genotype outcomes and their probabilities, such as when both parents are heterozygous for a single gene, yielding a 1:2:1 ratio. Other diagrams have different uses: a pedigree chart traces inheritance across a family, a karyotype shows chromosome number and structure, and gel electrophoresis separates DNA fragments.

Predicting offspring genotypes from parental alleles is best shown with a Punnett square. This diagram lays out the allele combinations that can appear in the next generation by placing one parent’s gametes along the top and the other parent’s gametes along the side, then filling each intersection with the resulting allele pair. It visually displays all possible genotype outcomes and their probabilities, such as when both parents are heterozygous for a single gene, yielding a 1:2:1 ratio. Other diagrams have different uses: a pedigree chart traces inheritance across a family, a karyotype shows chromosome number and structure, and gel electrophoresis separates DNA fragments.