What defines a monohybrid cross in genetics?

A monohybrid cross is specifically defined as a genetic cross that examines the inheritance of a single trait, typically involving two homozygous parents that express contrasting traits. For example, when crossing a pea plant with round seeds (homozygous dominant) with one that has wrinkled seeds (homozygous recessive), the offspring's traits are analyzed to understand how the alleles segregate and combine in subsequent generations.

This focus on one trait allows for the application of Mendelian principles to track inheritance patterns, such as dominant and recessive allele interactions. The classic example in genetics showcases how the first generation (F1) exhibits a dominant phenotype, while the second generation (F2) results in a phenotypic ratio indicative of both traits being represented, due to the segregation of alleles during gamete formation. Thus, the defining characteristic of a monohybrid cross is the investigation of inheritance patterns associated with a single trait derived from two homozygous parents.