Predicting Traits with Punnett Squares

7th GradeScience60 min

aligned to 7-ls1-6

Learning Objective

I can use a Punnett square to predict the probability of traits in offspring.

Lesson Flow

Watch Video

15 min

Mendelian Genetics and Punnett Squares

Professor Dave Explains

Guided Notes

12 min

Key concepts students will learn:

  • Gregor Mendel studied heredity using pea plants and determined that traits are passed on through discrete units called genes.

  • The F1 generation is the first filial generation, and the F2 generation is the second filial generation; Mendel observed trait expression, or phenotypes, up to the F2 generation.

  • A Punnett square uses a grid to show all possible combinations of alleles from two parents; homozygous organisms have identical alleles, while heterozygous organisms have one of each allele.

Practice

18 min

12 questions • Multiple choice & Short answer

Exit Ticket

5 min

A pea plant with round seeds (RR) is crossed with a pea plant with wrinkled seeds (rr). Use a Punnett square to determine the probability of the offspring having wrinkled seeds.

Teacher Guide

Get the complete package:

  • Answer keys for all questions
  • Differentiation strategies
  • Extension activities
  • Printable student handouts