What is the term for a cross between two individuals that differ by one trait?

The term that describes a cross between two individuals differing by one trait is known as a monohybrid cross. This type of genetic cross specifically examines the inheritance of a single trait and is commonly used in genetics to analyze the offspring ratios that result from the mating of two parents that are both heterozygous for that trait.

In a monohybrid cross, one can observe how a dominant trait manifests in the offspring in comparison to a recessive trait, typically following Mendel's laws of inheritance. By focusing solely on one trait, the genetic interactions are simplified, making it easier to predict the outcome of the traits observed in the progeny.

When considering the other terms, a dihybrid cross examines two traits simultaneously, requiring a more complex analysis of multiple alleles and their interactions. A test cross is used to determine the genotype of an individual with a dominant phenotype, crossing it with a homozygous recessive individual. A back cross involves crossing a hybrid individual back to one of its parents or an individual genetically similar to its parents, which is typically used to reinforce certain desired traits in future generations.