Introductory Genetics Series
Just the facts
Description of the fundamental concepts of trait inheritance in sexually reproducing species.
Segregation of Genes: The Plant Breeder's Method of Predicting the Future
How plant breeders create families with new combinations of traits and make predictions about the inheritance of traits. Discusses Mendel and Punnett.
The Inheritance of Variation
An introduction to genetic inheritance, including the principles of segregation and dominance.
The Dihybrid Cross and Independent Assortment
Examines the principle of segregation versus the principle of independent assortment and their effects on genetic data; and the concept of dominance.
Chi-Square Test for Goodness of Fit in a Plant Breeding Example
In plant breeding and genetics research, plant breeders establish a hypothesis to explain how they think a particular trait is inherited, such as if it is due to one gene with complete dominance, an interaction of more than one gene, or quantitative inheritance, with many genes contributing, etc. The question then is how do plant breeders determine if the data is close enough to what they expected to determine if the hypothesis is supported or not? Following a tomato disease resistance example in this lesson, you will learn a simple statistical test that breeders can use to conclude if the experimental data supports their hypothesis of single gene, completely dominant inheritance.
Evolution
This lesson describes an evolution story that is unfolding today in farmers fields around the world.
Mitosis and Meiosis and the Cell Cycle
Multicellular organisms such as plants and animals are composed of millions to trillions of cells that work together. This lesson details the steps of somatic cell division to produce identical cells by mitosis and germline cell division to produce gametes by meiosis. Emphasis is on what is happening genetically as these new cells are made in multicellular, sexually reproducing organisms.
Linkage - Part 1 - Biology and Mathematics of Linked Genes
You’ll learn to calculate basic map distances from dihybrid (two trait) data and combine map distances from multiple dihybrid crosses to make a linkage map.
Linkage - Part 2
Learn to make predictions about inheritance using map unit distances and genetic markers, assemble maps from multiple-point linkage data, define the relationship between linkage maps, linkage groups and genome maps, and describe how DNA or molecular markers are observed and used in gene mapping.
DNA and DNA Extraction
This lesson discusses what DNA is and how it relates to genes and chromosomes. How and why DNA is extracted in the genetic engineering process is also covered.
Electrophoresis: How scientists observe fragments of DNA
Describes gel electrophoresis and how the method is used in molecular genetic analysis.
Polymerase Chain Reaction (PCR)
The polymerase chain reaction (PCR) laboratory technique is used in a variety of applications to make copies of a specific DNA sequence. This lesson describes how a PCR reaction works, what it accomplishes and its basic requirements for success. Examples of interpreting results are given for a seed storage protein (kafirins in sorghum). PCR's strengths, weaknesses and applications to plant biotechnology are explained.
Real Time PCR - Some Basic Principles
Real time PCR is a laboratory technique that can perform relatively accurate, reliable and reproducible measurements, to quantitatively determine the presence of specific gene sequences. Its value is being recognized in a variety of applications, including transgenic (GMO) detection. It is becoming increasingly important to know what percentage of a particular transgene is present in an export shipment, for example. Real time PCR can also be used to support more traditional plant breeding techniques, making the process of distinguishing allelic variations more efficient. This lesson explains the principles of real time PCR and its' application, with examples in plant breeding and GMO detection.
Gene Expression Part 1: Reading Genes to Make Proteins
This lesson describes the steps involved in a cell as DNA sequence information is read to make RNA and RNA is read to make proteins.
Gene Cloning Part 2: Making and Screening Gene Libraries
This lesson teaches how a specific gene can be identified from among the thousands of genes that can be cloned from an organism.
Protein Detection in Plants
This lesson will focus on molecular principles involved in the detection of biotechnology derived proteins in crops, using the lateral flow ELISA.
Gene Cloning
This lesson covers the utilization of gene cloning to isolate and copy a specific gene of interest. The transformation of bacteria with plasmids containing antibiotic resistance genes to make gene libraries and the selection of bacteria colonies that contain the specific gene of interest are described.
Gene Cloning Part 1: The Mechanics of Recombinant DNA
This lesson describes how DNA molecules can be recombined to make recombinant DNA and how special DNA molecules called plasmids allow scientists to clone genes.
Gene Cloning Part 2: Making and Screening Gene Libraries
This lesson teaches how a specific gene can be identified from among the thousands of genes that can be cloned from an organism.
Transformation 1 - Plant Tissue Culture
This lesson explains the technique of tissue culture as used in plant transformation. It discusses important issues, such as the use of selectable markers, genotype specificity, and tissue culture alternatives.
Transformation 2 - Transformation Methods
This lesson explains the procedure of introducing a new gene into a plant cell (transformation). It discusses the main goals of the transformation process and describes the four main methods of transformation.
Transformation 3 - Transformation Events
This lesson defines an 'event'. It explains the determining factors specific to an event, the qualities of a desirable event, and the identification and selection of desirable events.