CH 1: Introduction (textbook)
Tuesday, August 30, 2022 1:41 PM
1.1 Genetics Is Important to Us Individually, to Society, and to the Study of Biology
Genetic Diversity and Evolution
• Genome—complete set of genetic instructions for any organism, and all genomes are
encoded in either DNA or RNA
Divisions of Genetics
• Transmission genetics—encompasses the basic principles of heredity and how traits are
passed from one generation to the next. Addresses the relation between chromosomes
and heredity, the arrangement of genes on chromosomes, and gene mapping. Focus on
the individual organism and how it passes its genes to the next generation
• Molecular genetics—focuses on the chemical nature of the gene itself: how genetic info is
encoded, replicated, and expressed. Focus on the gene and its structure, organization, and
function
• Population genetics—focuses on the genetic composition of populations and how that
changes geographically and with the passage of time
Model Genetic Organisms
• Organisms that are widely used in genetic research and can serve as models for genetic
systems of other organisms
1.2 Humans Have Been Using Genetic Techniques for Thousands of Years
The Early Use and Understanding of Heredity
• Pangenesis—believes that each part of the body contains genetic information for that
particular part. Specific particles carry information from various parts of the body to the
reproductive organs, from which they are passed to the embryo at the moment of
conception
• Preformationism—believes that inside the egg or sperm there exists a fully formed
miniature adult which simply enlarges with development. Means that all traits were
inherited from only one parent
• Blending inheritance—believes that the traits of offspring are a blend (or mixture) of
parental traits. Suggests that the genetic material itself blends and that genetic differences
could not be separated in future generations
The Rise of the Science of Genetics
• Cell theory—proposes that all life is composed of cells, cells only arise from preexisting
cells
• Germ-plasm theory—proposes that cells in the reproductive organs carry a complete set
of genetic information that is passed to the egg and sperm
• Mendelian inheritance—proposes that traits are inherited in accord with defined
principles
1.3: A Few Fundamental Concepts Are Important for the Start of Our Journey into Genetics
Tuesday, August 30, 2022 1:41 PM
1.1 Genetics Is Important to Us Individually, to Society, and to the Study of Biology
Genetic Diversity and Evolution
• Genome—complete set of genetic instructions for any organism, and all genomes are
encoded in either DNA or RNA
Divisions of Genetics
• Transmission genetics—encompasses the basic principles of heredity and how traits are
passed from one generation to the next. Addresses the relation between chromosomes
and heredity, the arrangement of genes on chromosomes, and gene mapping. Focus on
the individual organism and how it passes its genes to the next generation
• Molecular genetics—focuses on the chemical nature of the gene itself: how genetic info is
encoded, replicated, and expressed. Focus on the gene and its structure, organization, and
function
• Population genetics—focuses on the genetic composition of populations and how that
changes geographically and with the passage of time
Model Genetic Organisms
• Organisms that are widely used in genetic research and can serve as models for genetic
systems of other organisms
1.2 Humans Have Been Using Genetic Techniques for Thousands of Years
The Early Use and Understanding of Heredity
• Pangenesis—believes that each part of the body contains genetic information for that
particular part. Specific particles carry information from various parts of the body to the
reproductive organs, from which they are passed to the embryo at the moment of
conception
• Preformationism—believes that inside the egg or sperm there exists a fully formed
miniature adult which simply enlarges with development. Means that all traits were
inherited from only one parent
• Blending inheritance—believes that the traits of offspring are a blend (or mixture) of
parental traits. Suggests that the genetic material itself blends and that genetic differences
could not be separated in future generations
The Rise of the Science of Genetics
• Cell theory—proposes that all life is composed of cells, cells only arise from preexisting
cells
• Germ-plasm theory—proposes that cells in the reproductive organs carry a complete set
of genetic information that is passed to the egg and sperm
• Mendelian inheritance—proposes that traits are inherited in accord with defined
principles
1.3: A Few Fundamental Concepts Are Important for the Start of Our Journey into Genetics
