Predicting Trait Inheritance

Contributor: Hannah Brooks. Lesson ID: 12789

Mom has blue eyes and red hair. Dad is blond with brown eyes. Will their child have one brown and one blue eye with striped hair? Learn how scientists try to predict which traits children will have!


Life Science

learning style
Auditory, Visual
personality style
Grade Level
Middle School (6-8)
Lesson Type
Dig Deeper

Lesson Plan - Get It!

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  • Have you ever wondered how meteorologists can forecast the weather days in advance?

It's a fascinating process that involves gathering data, analyzing patterns, and making educated predictions.

  • But what does this have to do with eye color?

Just like meteorologists study atmospheric conditions to anticipate weather changes, scientists delve into the world of genetics to predict the inheritance of traits, such as eye color.

Get ready to unlock the secrets of trait inheritance as you dive into this captivating lesson!

Meteorologists use probability to estimate what weather patterns will move into an area.

They base their predictions on what has the most likelihood of happening. They develop a guess that is based on factual information and historical trends.

Scientists can use probabilities, or chances, to determine the likelihood that offspring inherit specific traits.

Physical appearance and genetic makeup are related, and some traits are considered dominant and can hide recessive alleles.

Scientists can use all this information to predict how traits are passed to offspring using a tool called a Punnett square, shown below.

punnett square

These simple tools allow scientists to illustrate how alleles separate during cell division and possible recombination during fertilization.

While you watch the Amoeba Sisters video below, complete their Video Recap: Monohybrid Crosses worksheet.

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Punnett squares can only be used for simple trait inheritance and cannot show complex combinations of traits or characteristics.

Each box in the Punnett square represents a 25% chance that the offspring has that genotype. Remember that dominant alleles will mask recessive alleles. If an offspring has the heterozygous genotype, they will have the dominant phenotype.

Before practicing these ideas in the next section, answer these questions.

  • What information does a Punnett square provide?
  • How might a Punnett square be useful for scientists and geneticists?
  • What are some limitations of the Punnett square?

Continue to the Got It? section to create your own animal using a Punnett square!

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