Copyright © 2010 Pearson Education Inc. Lecture 02 – Mendelian Genetics Based on Chapter 11 –...

Copyright © 2010 Pearson Education Inc.

Lecture 02 – Mendelian GeneticsBased on Chapter 11 – Mendelian Genetics

1. Introduction

2. Genotype and Phenotype

3a. Mendel’s Experimental Design

• Mendel used garden peas (Pisum sativum)• Established “true breeding” plants

– Now called inbred plants

• Carefully made crosses between true breeding lines

• Mathematically analyzed the results of the crosses and subsequent generations of plants.

3b. Mendel’s Experimental Design

4a. Monohybrid Crosses and Mendel’s Principle of Segregation

• Terminology used in breeding experiments:

• Parental generation is the P generation.

• Progeny of P generation is the first filial generation, designated F1.

• When F1 interbreed, the second filial generation, F2, is produced.

• Subsequent interbreeding produces F3, F4, and F5 generations.

4b. Monohybrid Crosses and Mendel’s Principle of Segregation

4c. Monohybrid Crosses and Mendel’s Principle of Segregation

4d. Monohybrid Crosses and Mendel’s Principle of Segregation

5a. The Principle of Segregation

5b. The Principle of Segregation

6a. Dihybrid Crosses and Mendel’s Principle of Independent Assortment

6b. Dihybrid Crosses and Mendel’s Principle of Independent Assortment 1.

6c. Dihybrid Crosses and Mendel’s Principle of Independent Assortment

6d. Dihybrid Crosses and Mendel’s Principle of Independent Assortment

6e. Dihybrid Crosses and Mendel’s Principle of Independent Assortment

The “Rediscovery” of Mendel’s Principles• Mendel’s work was published in 1866

– received little attention from the scientific community until about 1900

– Correns, deVries, and von Tschermark independently conducted experiments with similar results.

• In 1902 William Bateson, experimenting with fowl, showed that Mendelian principles apply in animals. – He coined the terms genetics, zygote, F1,

F2, and allelomorph (which was shortened to allele).

• W. L. Johannsen named Mendelian factors genes in 1909, from the Greek genos, meaning “birth.”

7a. Mendelian Genetics in Humans

7b. Mendelian Genetics in Humans

7c. Mendelian Genetics in Humans

7d. Mendelian Genetics in Humans