Agronomy and Horticulture Department
Just the Facts
Date of this Version
2001
Document Type
Article
Citation
Plant and Soil Sciences eLibrary (PASSeL) Lesson
Abstract
Description of the fundamental concepts of trait inheritance in sexually reproducing species.
Introduction
You have probably noticed that parents share many or most of their traits with their offspring. This observation came to the attention of humans long before scientific investigation developed. Human curiosity about the basis of trait inheritance is long standing, but most of what we know about genetics has emerged through research from the past 100 years. The fundamental concepts of trait inheritance in sexually reproducing species will be described in this lesson. The classical experimental approach that revealed these principles will be described in the following two lessons. For now, we will focus just on the facts of how variation is inherited.
Modules:
- Lesson home
- Introduction
- Concept 1: Sexually reproducing organisms make sex cells or gametes.
- Concept 2: Genes are stable, passed on in sex cells and control traits
- Concept 3: Genes are a part of the chromosome and are found in pairs in somatic cells.
- Concept 4: Genes can change on occasion and the alternative version or allele may control the trait
- Concept 5: Individuals can be homozygous or heterozygous.
- Concept 6: Gene pairs associate and then separate during gamete formation
- Concept 7: Gametes combine at random to form the individuals in the next generation.
- Concept 8: One allele can be dominant over another or show a lack of dominance.
- Concept 9: The segregation of genes allows geneticists to make predictions.
- Concept 10: Segregation can be predicted based on independent assortment.
Comments
Copyright © 2001 Don Lee and Patricia Hain. Used by permission.
This project was supported in part by the National Research Initiative Competitive Grants CAP project 2011-68002-30029 from the USDA National Institute of Food and Agriculture, administered by the University of California-Davis and by the National Science Foundation (NSF), Division of Undergraduate Education, National SMETE Digital Library Program, Award #0938034, administered by the University of Nebraska. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the USDA or NSF.
Development of this lesson was supported in part by Cooperative State Research, Education, & Extension Service, U.S. Dept. of Agriculture under Agreement Number 98-EATP-1-0403 administered by Cornell University and the American Distance Education Consortium (ADEC). Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the view of the U.S. Department of Agriculture.