13.1 Applied Genetics Selective Breeding Chapter 13 Genetics and Biotechnology 13.1 Applied Genetics Selective Breeding The process by which desired traits of certain plants and animals are selected and passed on to their future generations is called selective breeding. Saint Bernard Rescue dog Husky Sled dog German shepherd Service dog

Chapter 13 Genetics and Biotechnology 13.1 Applied Genetics Hybridization Hybrid organisms can be bred to be more disease-resistant, to produce more offspring, or to grow faster. A disadvantage of hybridization is that it is time consuming and expensive.

Pure breeds are maintained by inbreeding. Chapter 13 Genetics and Biotechnology 13.1 Applied Genetics Inbreeding The process in which two closely related organisms are bred to have the desired traits and to eliminate the undesired ones in future generations Pure breeds are maintained by inbreeding. A disadvantage of inbreeding is that harmful recessive traits also can be passed on to future generations.

Chapter 13 Genetics and Biotechnology 13.2 DNA Technology Genetic Engineering Technology that involves manipulating the DNA of one organism in order to insert the DNA of another organism, called exogenous DNA.

Genetically engineered organisms are used Chapter 13 Genetics and Biotechnology 13.2 DNA Technology Genetically engineered organisms are used to study the expression of a particular gene. to investigate cellular processes. to study the development of a certain disease. Genetically engineered bollworm to select traits that might be beneficial to humans.

An organism’s genome is the total DNA in the nucleus of each cell. Chapter 13 Genetics and Biotechnology 13.2 DNA Technology DNA Tools An organism’s genome is the total DNA in the nucleus of each cell. DNA tools can be used to manipulate DNA and to isolate genes from the rest of the genome.

Chapter 13 Genetics and Biotechnology 13.2 DNA Technology Restriction enzymes recognize and bind to specific DNA sequences and cleave the DNA within the sequence. Scientists use restriction enzymes as powerful tools for isolating specific genes or regions of the genome.

EcoRI specifically cuts DNA containing the sequence GAATTC. Chapter 13 Genetics and Biotechnology 13.2 DNA Technology EcoRI specifically cuts DNA containing the sequence GAATTC. The ends of the DNA fragments, called sticky ends, contain single-stranded DNA that is complementary.

The smaller fragments move farther faster than the larger ones. Chapter 13 Genetics and Biotechnology 13.2 DNA Technology An electric current is used to separate DNA fragments according to the size of the fragments in a process called gel electrophoresis. When an electric current is applied, the DNA fragments move toward the positive end of the gel. The smaller fragments move farther faster than the larger ones.

Chapter 13 Genetics and Biotechnology 13.2 DNA Technology Gel electrophoresis The unique pattern created based on the size of the DNA fragment can be compared to known DNA fragments for identification.

Chapter 13 Genetics and Biotechnology 13.2 DNA Technology The newly generated DNA molecule with DNA from different sources is called recombinant DNA.

Chapter 13 Genetics and Biotechnology 13.2 DNA Technology To make a large quantity of recombinant plasmid DNA, bacterial cells are mixed with recombinant plasmid DNA. Some of the bacterial cells take up the recombinant plasmid DNA through a process called transformation.

Chapter 13 Genetics and Biotechnology 13.2 DNA Technology Large numbers of identical bacteria, each containing the inserted DNA molecules, can be produced through a process called cloning.

Chapter 13 Genetics and Biotechnology 13.2 DNA Technology A technique called the polymerase chain reaction (PCR) can be used to make millions of copies of a specific region of a DNA fragment.

Chapter 13 Genetics and Biotechnology 13.2 DNA Technology Biotechnology Organisms, genetically engineered by inserting a gene from another organism, are called transgenic organisms.

Mice, fruit flies, and the roundworm Chapter 13 Genetics and Biotechnology 13.2 DNA Technology Transgenic Animals Scientists produce most transgenic animals in laboratories for biological research. Mice, fruit flies, and the roundworm

Genetically engineered cotton resists insect infestation of the bolls. Chapter 13 Genetics and Biotechnology 13.2 DNA Technology Transgenic Plants Genetically engineered cotton resists insect infestation of the bolls. Sweet-potato plants are resistant to a virus that could kill most of the African harvest. Rice plants with increased iron and vitamins could decrease malnutrition.

The Human Genome Project Chapter 13 Genetics and Biotechnology 13.3 The Human Genome The Human Genome Project The goal of the Human Genome Project (HGP) was to determine the sequence of the approximately three billion nucleotides that make up human DNA and to identify all of the approximately 20,000–25,000 human genes.

These regions are called noncoding sequences. Chapter 13 Genetics and Biotechnology 13.3 The Human Genome Less than two percent of all of the nucleotides in the human genome code for all the proteins in the body. The genome is filled with long stretches of repeated sequences that have no direct function. These regions are called noncoding sequences.

Protein-coding regions of DNA are almost identical among individuals. Chapter 13 Genetics and Biotechnology 13.3 The Human Genome DNA Fingerprinting Protein-coding regions of DNA are almost identical among individuals. The long stretches of noncoding regions of DNA are unique to each individual. DNA fingerprinting involves separating these DNA fragments to observe the distinct banding patterns that are unique to every individual.

Creating and maintaining databases of biological information Chapter 13 Genetics and Biotechnology 13.3 The Human Genome Bioinformatics Creating and maintaining databases of biological information Finding genes in DNA sequences of various organisms and developing methods to predict the structure and function of newly discovered proteins

Chapter 13 Genetics and Biotechnology 13.3 The Human Genome The study of how genetic inheritance affects the body’s response to drugs is called pharmacogenomics. The benefits of pharmacogenomics include more accurate dosing of drugs that are safer and more specific.

A technique aimed at correcting mutated genes Chapter 13 Genetics and Biotechnology 13.3 The Human Genome A technique aimed at correcting mutated genes that cause human diseases is called gene therapy. Scientists insert a normal gene into a chromosome to replace a dysfunctional gene. Genomics is the study of an organism’s genome.