Final answer:
The question involves a genetic cross with three contrasting traits, using principles of segregation and independent assortment. While a Punnett square is a common tool for such analyses, the forked-line diagram is a preferable, simpler method for trihybrid crosses, circumventing the need for large Punnett squares.
Step-by-step explanation:
Understanding Genetic Crosses and Tools
The student's question pertains to a type of genetic cross involving three pairs of contrasting traits, following the principles of segregation and independent assortment. A Punnett square that would display such a cross with three traits (trihybrid) would indeed have 64 boxes. However, an alternative and simpler method for analyzing the outcomes of this cross would be the forked-line diagram. The forked-line method dramatically reduces complexity by using branching pathways to represent the independent assortment of alleles. For instance, a cross resulting from heterozygous F₁ parents with genotypes AABBCC and aabbcc would entail segregating each pair of alleles into probabilities for each trait separately and then combining those probabilities using the product rule to determine the F₂ offspring probabilities.
To illustrate independent assortment with a dihybrid cross, where two traits are considered, we could use a 4x4 Punnett square to show the genotypic combinations, and from these, determine the phenotypic ratios. However, as more traits are analyzed, the Punnett square becomes unwieldy, necessitating alternatives like the forked-line method, especially when dealing with traits that assort independently.