Chapter 12 Assessment

How could manipulating DNA be beneficial?

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

Hybridization Genetics and Biotechnology  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. Chapter 13

Inbreeding Genetics and Biotechnology  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.  Disadvantage - harmful recessive traits also can be passed on to future generations Applied Genetics Chapter 13

 A test cross involves breeding an organism that has the unknown genotype with one that is homozygous recessive for the desired trait. Genetics and Biotechnology Test Cross 13.1 Applied Genetics Chapter 13

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

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

DNA Tools Genetics and Biotechnology  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 DNA Technology Chapter 13

Genetics and Biotechnology  Scientists use restriction enzymes to isolate specific genes or regions of the genome. Chapter 13  Restriction enzymes recognize and bind to specific DNA sequences and cleave the DNA within the sequence.

Genetics and Biotechnology 13.2 DNA Technology Chapter 13

Genetics and Biotechnology  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 DNA Technology Chapter 13

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

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

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

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

Genetics and Biotechnology Biotechnology  Organisms, genetically engineered by inserting a gene from another organism, are called transgenic organisms DNA Technology Chapter 13  Scientists produce most transgenic animals in laboratories for biological research.

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. Genetics and Biotechnology 13.3 The Human Genome Chapter 13

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

DNA Fingerprinting Genetics and Biotechnology  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. Chapter 13

DNA Microarrays Genetics and Biotechnology  Tiny microscope slides or silicon chips that are spotted with DNA fragments  Help researchers determine whether the expression of certain genes is caused by genetic factors or environmental factors The Human Genome Visualizing Microarray Analysis Chapter 13

Genetics and Biotechnology  Variations in the DNA sequence that occur when a single nucleotide in the genome is altered are called single nucleotide polymorphisms or SNPs The Human Genome Chapter 13

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

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

 Genes are the primary information storage units, whereas proteins are the machines of a cell. Genetics and Biotechnology 13.3 The Human Genome Chapter 13

Quiz Analyze how DNA technology is used in forensics, agriculture, and medicine.