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Mendelian Inheritance

Mendelian Inheritance

Mendelian inheritance refers to patterns of inheritance that are characteristic of organisms that reproduce sexually. The Austrian monk Gregor Mendel performed thousands of crosses with garden peas at his monastery during the middle of the 19th century. Mendel explained his results by describing two laws of inheritance that introduced the idea of dominant and recessive genes.

Mendelian Inheritance
Images and animations are courtesy of the National Human Genome Research Institute's Talking Glossary (

Materials for Mendelian Inheritance


Major Color Locus

Description: Learn how sex linked genes determine the color of a pigeons feathers.

Sex Linkage

Description: Males and females inherit different sex chromosomes - a fact that must be considered when making predictions about X and Y linked traits.

What are Dominant and Recessive Alleles?

Description: Different versions of a gene are called alleles. Alleles are described as either dominant or recessive depending on their associated traits.

What Are Single Gene Disorders?

Description: Single gene disorders are caused by DNA changes in one particular gene, and often have predictable inheritance patterns.

Wing Pattern

Description: Learn in detail how alleles (versions of a gene) influence the pattern of feathers on a pigeon.

Interactive Tutorials

Gene Screen App

Description: An app that helps you learn how recessive genetic traits and diseases are inherited and how certain diseases are more prevalent in different populations.

Mendelian Laws Apply to Human Beings

Description: An interactive Web site exploring concepts of mendelian inheritance through historical discovery

The Biology Place - Mendelian Inheritance

Description: Information, interactive practice activities, and a quiz on Mendelian inheritance

Teacher Resources

Introduction to Heredity and Traits (Lesson Plans/Lesson Activities)

Description: Five easy-to-implement clasroom activities teach the basics of heritable traits. Three take-home activities help students share what they're learning with their families.

Pigeonetics Guide (Lesson Plans/Lesson Activities)

Description: This game, with 26 pigeon-breeding puzzles of increasing complexity, helps students learn about mechanisms of inheritance, and it brings together often disconnected concepts from Mendelian inheritance and molecular genetics.

Sex Determination (Lesson Plans/Lesson Activities)

Description: This lesson explores sex determination in mammals. Students first share their conceptions about the genetics of sex determination, then using normal and abnormal human karyotypes, students hone in on their hypothesis. The case of XY females is used to explain the presence of the SRY gene on the Y chromosome, which must produce active protein in order for a male to develop. The lesson ends by exploring other sex-determination systems in animals and their similarities and differences.

Sex-Linked Inheritance (Lesson Plans/Lesson Activities)

Description: In this lesson, students take on the role of scientists as they explore the results of T.H. Morgan's famous white-eyed flies experiment. Students construct Punnett squares for different hypotheses in order to determine which hypothesis fits Morgan's actual results. Students work toward an understanding that white eyes in flies are an X-linked recessive trait. They explore the hallmarks of this type of sex-linked inheritance as well as the much rarer types, X-linked dominant and Y-linked.


Introduction to Mendelian Genetics

Description: Mendel used experimental approaches to characterize a particulate model of inheritance. In doing so, he developed the three Laws of Inheritance. Examine how Mendel made his important discoveries.

Mendelian Genetics

Description: A video on Mendelian inheritance

Mendelian Genetics and Inheritance

Description: A video on Mendelian inheritance

Gregor Mendel's Peas


Some Genes are Dominant

Description: An animation on Mendels pea experiments and the principle of dominance


Experiments in Plant Hybridization by Gregor Mendel 1865 (PDF 199.79 KB)

Description: The original Mendel paper.

Genetics: Gregor Mendel

Description: Information on Gregor Mendel's experiments and punnet square exercises

Gregor Mendel - A Private Scientist

Description: A brief history on the life of Gregor Mendel

Gregor Mendel and the Principles of Inheritance

Description: A 2008 research journal paper from Nature Education. A must read in preparing for advanced classes. This paper covers traits, alleles, crosses, and assortment.

Gregor Mendel's Garden

Description: View a picture of Gregor Mendel's garden.

Interactive Tutorials

Children Resemble Their Parents

Description: Information, videos, interactive tutorials, and animations on genetic traits

Genes Are Real Things

Description: An interactive Web site exploring basic concepts of cells and genes through historical discovery

Genes Come in Pairs

Description: An interactive Web site exploring basic principles of traits and genes through Mendel's experiments

Genetic Inheritance Follows Rules

Description: An interactive Web site exploring basic concepts of genetic inheritance through historical discovery

Some Genes Are Dominant

Description: An interactive Web site exploring basic concepts of genetic traits and inheritance through Mendel's experiments

Labs & Experiments

Mendelian Inheritance

Description: A virtual laboratory experiment teaching concepts of Mendelian inheritance and genetic variation

Teacher Resources

A Mendel Seminar (Lesson Plans/Lesson Activities)

Description: Students learn about Gregor Mendel. Mendel discovered the process of biological evolution, how recessive and dominant traits are passed on.


Gregor Mendel - Great Minds

Description: A witty 11 minute video on the childhood and life of Mendel.

Gregor Mendel - My Favourite Scientist

Description: A detail rich 6-minute TEDEd video biography of Mendel using expert narration and youthful illustrations.

How Mendel Helped Us Understand Genetics

Description: A playful 3 minute animated video that explains how studying pea plants helped solve the mystery of inheritance.