The kind of diagram that shows the probability of traits in offspring is called a Punnett square. It is a square chart used by biologists to predict the genotypes and phenotypes resulting from a genetic cross between two parents. The diagram displays all possible combinations of alleles that offspring can inherit, allowing calculation of the probability of each genotype and trait

. Key features of a Punnett square:

• It arranges the gametes (alleles) from each parent along the top and side of the square.
• Each cell inside the square represents a possible genotype of the offspring from the combination of parental alleles.
• By analyzing the genotypes, one can determine the probability of offspring having dominant or recessive traits.
• It is especially useful for monohybrid crosses involving a single gene with dominant and recessive alleles

For example, crossing two heterozygous parents (Tt) for a trait results in offspring genotypes TT, Tt, and tt with probabilities 25%, 50%, and 25%, respectively, which translates to a 3:1 ratio of dominant to recessive phenotypes

. Thus, a Punnett square is the standard diagram used to show the probability of traits in offspring in genetics.