Chapter 13 Genetics and Biotechnology

2. Chapter 13 Genetics and Biotechnology Section 1: Applied Genetics Section2: DNA Technology Section 3: The Human Genome

3. Genetics and Biotechnology Chapter 13 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

4. Genetics and Biotechnology Chapter 13 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.

5. Genetics and Biotechnology Chapter 13 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.

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

7. Genetics and Biotechnology Chapter 13 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.

8. Genetics and Biotechnology Chapter 13 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.

9. Genetics and Biotechnology Chapter 13 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.

10. Genetics and Biotechnology Chapter 13 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.

11. Genetics and Biotechnology Chapter 13 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.

12. Genetics and Biotechnology Chapter 13

13. Genetics and Biotechnology Chapter 13 13.2 DNA Technology • Anelectric 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.

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

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

16. Genetics and Biotechnology Chapter 13 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.

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

18. Genetics and Biotechnology Chapter 13 13.2 DNA Technology • To understand how DNA is sequenced, scientists mix an unknown DNA fragment, DNA polymerase, and the four nucleotides—A, C, G, T in a tube.

19. Genetics and Biotechnology • Every time a modified fluorescent-tagged nucleotide is incorporated into the newly synthesized strand, the reaction stops. Chapter 13 13.2 DNA Technology • Each nucleotide is tagged with a different color of fluorescent dye.

20. Genetics and Biotechnology Chapter 13 13.2 DNA Technology • The sequencing reaction is complete when the tagged DNA fragments are separated by gel electrophoresis.

21. Genetics and Biotechnology Chapter 13 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.

22. Genetics and Biotechnology Chapter 13

23. Genetics and Biotechnology Chapter 13 13.2 DNA Technology

24. Genetics and Biotechnology Chapter 13

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

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

27. Genetics and Biotechnology Chapter 13 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. Gene Splicing

28. Genetics and Biotechnology Chapter 13 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.

29. Genetics and Biotechnology Chapter 13 13.3 The Human Genome Sequencing the Genome • Each of the 46 human chromosomes was cleaved. • These fragments were combined with vectors to create recombinant DNA, cloned to make many copies, and sequenced using automated sequencing machines. • Computers analyzed the overlapping regions to generate one continuous sequence.

30. Decoding the sequence of the human genome can be compared to Genetics and Biotechnology reading a book that was printed in code. Chapter 13 13.3 The Human Genome

31. Genetics and Biotechnology Chapter 13 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.

32. Genetics and Biotechnology Chapter 13 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.

33. Genetics and Biotechnology Chapter 13 13.3 The Human Genome Identifying Genes • Researchers have identified genes by scanning the sequence for Open Reading Frames (ORFs). • ORFs contain at least 100 codons that begin with a start codon and end with a stop codon.

34. Genetics and Biotechnology Chapter 13 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

35. Genetics and Biotechnology Chapter 13 13.3 The Human Genome DNA Microarrays • 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.

36. Genetics and Biotechnology Chapter 13

37. Genetics and Biotechnology Chapter 13 13.3 The Human Genome • Variations in the DNA sequence that occur when a single nucleotide in the genome is altered are called single nucleotide polymorphisms or SNPs.

38. Genetics and Biotechnology Chapter 13 13.3 The Human Genome • Regions of linked variations in the human genome are known as haplotypes. • Assembling the HapMap involves identifying groups of SNPs in a specific region of DNA.

39. Genetics and Biotechnology Chapter 13 13.3 The Human Genome • The HapMap will enable geneticists to take advantage of how SNPs and other genetic variations are organized on chromosomes.

40. Genetics and Biotechnology Chapter 13 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.

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

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

43. Genetics and Biotechnology Chapter 13 13.3 The Human Genome • The large-scale study and cataloging of the structure and function of proteins in the human body is called proteomics.

44. Genetics and Biotechnology Chapter 13 Chapter Resource Menu Chapter Diagnostic Questions Formative Test Questions Chapter Assessment Questions Standardized Test Practice biologygmh.com Glencoe Biology Transparencies Image Bank Vocabulary Animation Click on a hyperlink to view the corresponding feature.

45. A B C D Genetics and Biotechnology Chapter 13 CDQ 1 Chapter Diagnostic Questions Which statement is not true of hybridization? It is relatively inexpensive to perform. It produces offspring with specific traits. It crosses a parent organism with different forms of a trait. It can take a long time to be successful.

46. A B C D Genetics and Biotechnology Chapter 13 CDQ 2 Chapter Diagnostic Questions Name the process that scientists use to separate DNA fragments according to size. genetic engineering gel electrophoresis cleaving selective breeding

47. A B C D Genetics and Biotechnology Chapter 13 CDQ 3 Chapter Diagnostic Questions Select the process in which one type of bacterium takes up the DNA from another type of bacterium. cloning sequencing transformation manipulation

48. A B C D Genetics and Biotechnology Chapter 13 FQ 1 13.1 Formative Questions Which term explains how humans have been able to produce a wide variety of domestic cats? homogenization inbreeding selective breeding test crossing

49. A B C D Genetics and Biotechnology Chapter 13 FQ 2 13.1 Formative Questions A new breed of cattle has been developed by crossing English Shorthorn cattle, which provide good beef but cannot withstand hot environments, and Brahman cattle from India that have a high heat tolerance but produce poor beef. The new breed, Santa Gertrudis, produces excellent beef and can live in hot environments. Which term describes Santa Gertrudis cattle? cross breed hybrid outbred purebred

50. A B C D Genetics and Biotechnology Chapter 13 FQ 3 13.1 Formative Questions Harmful recessive traits can be passed through generations of purebred animals as a result of _______. hybridization inbreeding line breeding out crossing