How to Determine Genotype

Step-by-Step Guide

1. 1

   Step 1: Draw a 2x2 square.

   A Punnett square is used to determine the likelihood of an offspring’s genotype based on the genotypes of its parents.
   
   The square will be labeled with the genotype of each parent.
   
   Within the square, the possible genotypes of the offspring will be shown., Take the genotype of one parent and split the two letters (representing dominant and recessive traits).
   
   Place one letter to the left of the top row, and one letter to the left of the bottom row.
   
   This will represent that parent’s contribution to the offspring’s genotype.It is customary to put a dominant trait (capital letter) on the top row and a recessive trait (lowercase letter) on the bottom if the two traits are different. , The other parent’s traits should be split in the same way.
   
   This time, place one letter in above the left column, and the other above the right column.
   
   This will represent the second parent’s contribution to the offspring’s genotype.It is customary to put a dominant trait (capital letter) on the left and a recessive trait (lowercase letter) on the right if the two traits are different. , Each square can now be filled.
   
   Inside each square, write the letter that corresponds to the row that the square is in.
   
   Next, write the letter that corresponds to the column the square is in.
   
   This will identify all possible genotypes for the offspring as well as the percentage at which they would occur.For mixed traits, write the genotype so that the dominant trait is listed first (Rr instead of rR).
2. 2

   Step 2: Label the left side.

3. 3

   Step 3: Label the top.

4. 4

   Step 4: Input known information.

Detailed Guide

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