Punnett squares are a great tool to see how parents pass traits to their offspring.

Think of them like a simple way to guess what traits kids will have, based on Mendelian genetics. This means we look at the basic ideas of dominant and recessive genes.

What is a Punnett Square?

A Punnett square is like a grid that shows all the possible gene combinations that can come from a cross between two parents.

For example, let’s say you are breeding pea plants. One plant has two dominant genes ($AA$), and the other has two recessive genes ($aa$). You would draw a square and use the rows and columns to represent each parent’s genes.

How to Set It Up

1. Identify the Genes: First, you need to know the genes you’re looking at. For flower color, let’s say:

   • $A$: dominant gene (purple flowers)
   • $a$: recessive gene (white flowers).

2. Draw the Square: Make a 2x2 grid. Write one parent's genes across the top and the other parent's genes down the side.

        A      A   
     ------------
   a |   Aa   Aa  
   a |   Aa   Aa  
   

3. Fill in the Grid: Combine the genes from each row and column to see the gene makeup of the offspring.

Understanding the Results

In this example, all the offspring have the gene makeup $Aa$, which means they will have purple flowers since $A$ is the dominant gene.

If you had two plants both with the $Aa$ gene setup, the square would look different. You would then see a mix of:

• 1 $AA$: 2 $Aa$: 1 $aa$.

This means there’s a 75% chance of purple flowers and a 25% chance of white flowers.

Why Use Punnett Squares?

Punnett squares are a fast and easy way to guess what traits baby plants or animals might have. They help you not only see the expected looks (phenotypes) but also the genes (genotypes) inside.

Using Punnett squares makes understanding how traits are passed down much clearer and simpler. Whether you're curious about flower colors or genetic conditions, they are a handy visual tool to help you learn about inheritance!