Unit 1: Introduction to Punnett Squares

Unit 1: Introduction to Punnett Squares

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Objectives and Instructions

Lesson Objective:

Given a word problem regarding inheritance of a widow’s peak trait, the learner will be able to identify the genotype of both parents then properly develop a Punnett square with parental alleles.



Please watch the video tutorial to learn about the basics of Punnett squares. Using that information complete the practice problems below the video and score yourself using the key provided to check your understanding of the concepts. When you feel confident in your understanding of the concepts, complete the 5 quiz questions in the upper right corner of this page.


Have you ever wondered why some members of a family look similar? Or why exactly your eyes are blue or your hair is brown? The reason for this is related to your genes. Genes are bits of genetic information passed down from parents to offspring. In genetics we can use a basic tool called a Punnett square to predict the outcome of offspring when we know the genes of the parents. Below is an example of what a Punnett square looks like. In order to set up a Punnett square you must know the genotypes (letters used to represent alleles) of the parents. The video tutorial for this unit will give you more details on basic concepts of heredity and how to set up a Punnett square. 




Video Instruction

Practice Problems

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