What kind of diagram shows the probability of traits in an offspring?
A Punnett square.
The kind of diagram that shows the probability of traits in an offspring is called a Punnett square. A Punnett square is a graphical representation used by geneticists to predict the probability of different genotypes and phenotypes in the offspring based on the genetic information of the parents.
To create a Punnett square, you need to know the genotypes of both parents. Each parent's genotype is represented by two alleles — one inherited from each parent. For simplicity, let's consider a simple scenario of a single trait with two possible alleles, represented by uppercase and lowercase letters.
Step 1: Determine the Parental Genotypes
Identify the alleles present in each parent. For example, let's say one parent is homozygous dominant (AA) and the other parent is heterozygous (Aa).
Step 2: Create the Punnett Square
Create a 2x2 grid, with the alleles of the parents written along the top and left side of the grid. Fill in the grid by combining the alleles from the parent row-wise and column-wise.
| A | a |
--------------------------------
A | AA | Aa |
--------------------------------
a | Aa | aa |
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Step 3: Determine the Offspring Genotypes
The individual boxes in the Punnett square represent the potential genotypes of the offspring. By reading the combinations in each box, you can determine the probability of specific genotypes in the offspring. In this example, the possible genotypes are AA, Aa, Aa, and aa.
Step 4: Calculate the Phenotypic Ratios
Once you have determined the genotypes of the offspring, you can calculate the probability of specific phenotypes by considering the trait's inheritance pattern. For instance, if uppercase A represents a dominant trait and lowercase a represents a recessive trait, then the offspring with the genotype AA and Aa would both exhibit the dominant trait, while the offspring with the genotype aa would exhibit the recessive trait.
By following these steps and using a Punnett square, you can visually display and calculate the probability of different genotypes and phenotypes in the offspring.