Name Date lass Master 19 Basic oncepts Recombinant DN Use with hapter, Section.2 Formation of Recombinant DN ut leavage Splicing opyright lencoe/mcraw-hill, a division of he Mcraw-Hill ompanies, Inc. Bacterial chromosome loning of Recombinant DN in Bacteria leavage site Plasmid Bacterial plasmids Foreign DN (gene for insulin) Recombined plasmid ransgenic cell Insulin Reproduction E. coli Numerous daughter cells with recombinant DN UNI 4 HPER enetic echnology 9
Name Date lass Worksheet 19 Recombinant DN Basic oncepts Use with hapter, Section.1 1. What is the purpose of the cleavage step shown in the transparency? 2. What is the role of bacterial proteins in DN cleavage? 3. Describe the sequence of bases in the sticky ends of a cleaved double strand of DN. 4. What happens as a result of gene splicing? 5. What is the function of the plasmid in the cloning technique shown in the transparency? 6. How are the cleaved DN fragments from two sources able to recombine? 7. Where on the transparency does cloning occur? opyright lencoe/mcraw-hill, a division of he Mcraw-Hill ompanies, Inc. 140 HPER enetic echnology UNI 4
Name Date lass Master 22 Recombinant DN echnique Reteaching Skills Use with hapter, Section.2 Bacterium (prokaryotic cell) Eukaryotic cell (a) Plasmid extracted (b) Plasmid and donor DN treated with same restriction enzyme (a) Donor DN extracted Specific cleavage sites (producing sticky ends ) Specific cleavage sites (producing sticky ends ) opyright lencoe/mcraw-hill, a division of he Mcraw-Hill ompanies, Inc. (d) Plasmid introduced into new bacterium lones of recombinant bacterium (c) he donor gene sequence is spliced into the plasmid by matching sticky ends. (e) Spliced DN replicates along with bacterial DN. (f) Eukaryotic gene product isolated and collected in large amounts UNI 4 HPER enetic echnology 141
Name Date lass Worksheet 22 Recombinant DN echnique Reteaching Skills Use with hapter, Section.2 1. Define these terms: a. transgenic organism b. recombinant DN c. vector 2. List the two types of vectors used in recombinant DN technology, and give examples of each. 3. How are restriction enzymes important tools in genetic engineering? 4. What is a plasmid? 5. Why is it essential that both the plasmid and the donor DN be exposed to the same restriction enzyme? 6. What must researchers know before they begin the process of genetic engineering? 7. Why does producing a single bacterium through genetic recombination enable researchers to produce large numbers of bacteria with the recombined plasmid? opyright lencoe/mcraw-hill, a division of he Mcraw-Hill ompanies, Inc. 8. What would be the goal of a researcher who inserted the gene for insulin into bacteria? 142 HPER enetic echnology UNI 4
Name Date lass hapter enetic echnology hapter ssessment Reviewing Vocabulary Write the word or phrase that best completes the statement. Use these choices: human genome transgenic organisms linkage map gene therapy vectors restriction enzymes plasmid inbreeding testcross 1. are used to cut DN into fragments. 2. is based on the insertion of normal genes into cells with defective genes in an attempt to correct genetic disorders. 3. he entire collection of genes within human cells is referred to as the. 4. (n) is a small, circular piece of DN found in bacterial cells. 5. (n) shows the location of genes on a chromosome. 6. are produced when DN from another species is inserted into the genome of an organism, which then begins to use the foreign DN as its own. 7. (n) is a cross of an individual of unknown genotype with an individual of known genotype. opyright lencoe/mcraw-hill, a division of he Mcraw-Hill ompanies, Inc. 8. gene gun and a virus may both be classified as because they are mechanisms by which foreign DN may be transferred into a host cell. 9. is mating between closely related individuals. Explain the following terms. Use complete sentences. 10. genetic engineering 11. gene splicing 12. recombinant DN UNI 4 HPER enetic echnology 143
Name Date lass hapter enetic echnology, continued hapter ssessment Understanding Main Ideas (Part ) In the space at the left, write the letter of the word or phase that best completes the statement or answers the question. 1. small amount of DN obtained from a mummy or from a human long frozen in glacial ice may be cloned through a. polymerase chain reaction techniques. b. gel electrophoresis. c. DN fingerprinting. d. gene splicing. 2. Examine the piece of DN represented in the figure at the right. he nucleotide sequences on both strands, but running in opposite directions, are in an arrangement called a a. vector b. chromosome mutation. c. palindrome. d. transgenic codon. 3. ransgenic bacteria are currently used to produce a. human growth hormone and insulin. b. human growth hormone and interferon. c. hexosaminidase and insulin. d. insulin and interferon. 4. el electrophoresis is a technique used to a. clone chromosomes of various species. b. cut DN into fragments of various sizes. c. separate DN fragments by length. d. inject foreign DN into animal and plant cells. 5. Bone marrow cells with a defective gene are removed from a donor and grown in a sterile flask. Virus vectors with the corrected gene are integrated into the bone marrow cells. he changed bone marrow cells are returned to the donor. his is an attempt at a. palindrome formation. b. gene therapy. c. DN fingerprinting. d. linkage mapping. 6. How might a breeder determine if a certain golden retriever is a carrier of an undesirable trait? a. prepare a linkage map b. perform a testcross c. clone the dog d. splice the undesirable allele into the dog s genome opyright lencoe/mcraw-hill, a division of he Mcraw-Hill ompanies, Inc. 144 HPER enetic echnology UNI 4
Name Date lass hapter enetic echnology, continued hapter ssessment Understanding Main Ideas (Part B) In the space at the left, write the letter of the word or phase that best completes the statement or answers the question. 1. linkage map such as the one illustrated in the figure at the right, for human chromosome number 4, can be produced as a result of a. a study of antigen-antibody reactions and PR. b. a determination of the frequency with which the genes occur together. c. a process called karyotyping. d. both karyotyping and palindrome formation. Huntington s disease typical PKU Serum album Red hair color opyright lencoe/mcraw-hill, a division of he Mcraw-Hill ompanies, Inc. 2. Below follows a list of procedures involved in the production of a transgenic organism. From the choices provided, what is the sequence that represents the proper order of events?. Recombinant DN is transferred into a suitable host. B. desirable gene is identified in a DN sequence.. he DN fragment to be inserted is joined with a carrier to transport it. D. he DN fragment to be inserted is isolated. a., B,, D b. B,,, D c. B, D,, d. D,, B, In 1973, Stanley ohen and Herbert Boyer inserted a gene from an frican clawed frog into a bacterium. he bacterium produced the protein coded for by the inserted frog gene. 3. In their experiment, ohen and Boyer produced a DN molecule composed of both frog DN and bacterial DN. Because the new genetic material consisted of DN from two different organisms, it can be referred to as a. recombinant DN. b. a linkage map. c. a vector. d. gene therapy. 4. his insertion of a small fragment of frog DN into the DN of another species can most accurately be called a. cloning. b. genetic engineering. c. electrophoresis. d. gene therapy. 5. t the conclusion of the experiment, a bacterium containing functional frog DN would be classified as a a. clone. b. DN fingerprint. c. plasmid. d. transgenic organism. UNI 4 HPER enetic echnology 145
Name Date lass hapter enetic echnology, continued hapter ssessment hinking ritically Read the paragraph below. hen answer the questions that follow. grobacterium tumefaciens is a bacterium that causes crown gall disease, a tumorous growth on the growing tip of certain plants. he bacterium is able to enter a plant through small cuts in the outer cell layer. When grobacterium enters a plant cell, a DN sequence from the bacterium integrates into the plant s DN. his new section of DN causes the plant s cell to reproduce quickly to form a tumor and to synthesize a food molecule needed by the bacterium. critical bit of information that scientists have learned about the process is that the tumor-causing information is carried on a large plasmid that is separate from the bacterium s main chromosome. During the infection process, the DN on the plasmid that codes for food production and rapid reproduction leaves the plasmid, moves into the plant cell nucleus, and integrates with one of the plant cell s chromosomes. hus, when the plant cell reproduces, it passes along the bacterium s genetic information, which has been incorporated into the plant genome. 1. Why is the above information about how grobacterium causes crown gall disease important to scientists hoping to produce transgenic plants? 2. What could be used to cut open an grobacterium plasmid and insert a gene that would increase the rate of conversion of atmospheric nitrogen into nitrates? 3. Illustrate and label what the plasmid might look like with the desired gene inserted. 4. What benefits to agriculture could come from scientists being able to engineer plants genetically? opyright lencoe/mcraw-hill, a division of he Mcraw-Hill ompanies, Inc. 146 HPER enetic echnology UNI 4
Name Date lass hapter enetic echnology, continued hapter ssessment opyright lencoe/mcraw-hill, a division of he Mcraw-Hill ompanies, Inc. pplying Scientific Methods t the DN level, humans are very similar, and the genes that code for their proteins follow fairly standard patterns. However, the segments of noncoding DN found between the genes referred to as junk DN follow patterns that vary from one individual to another. For example, in Individual the junk DN base sequence represented by (cytosine, adenine, and thymine) could be repeated 3 times () in one place in that individual s genome and 6 times in another place. In Individual B, the same noncoding DN sequence could form a different pattern, with 10 repetitions of in one place and 30 repetitions in another. In a given population, there may be a large number of segments of DN that differ on the basis of the noncoding DN pattern. herefore, if Individuals and B have a child, the child is likely to be heterozygous for the segments of DN involving noncoding sequences. he patterns of noncoding DN sequences give all individuals (except identical twins) a distinctive fingerprint. he fingerprint is constructed by isolating DN from a few cells, cutting it into fragments using restriction enzymes, and sorting the fragments by size using gel electrophoresis. he shorter the DN fragment, the farther it will migrate through the gel. he result is a visual representation of an individual s DN, or a DN fingerprint. DN fingerprint can be used to identify a child s biological father. he basis for such an identification is that a repetitive, noncoding sequence present in the child but not found in the mother must have been inherited from the father. Examine the bands in the diagram of the DN fingerprints shown below. Each band represents a fragment of DN. he first vertical lane of bands represents standard markers of known size, which are used as a reference. o the right of the standard markers is the lane of bands representing the child s DN fingerprint. he next lane is the mother s DN, followed by the DN fragments from two men who might be the child s father. Study the pattern of each lane of DN bands. hen answer the questions. Standard Markers B D E F Mother hild Suspected fathers #1 #2 DN bands Wells for injecting DN Direction of movement UNI 4 HPER enetic echnology 147
Name Date lass hapter enetic echnology, continued hapter ssessment pplying Scientific Methods continued 1. Which location represents the longest DN fragment? Which location represents the shortest fragment? Explain. 2. Which of the men, Father #1 or Father #2, is probably the biological father of the baby? Explain. 3. What would be indicated if you saw only one band in a lane? 4. Below is a drawing of a hypothetical gel. Included on the gel is the banding pattern of the mother and father of two children. Draw what the pattern of bands for each of the children might look like. Indicate the possible parental source using for the male (father) and for the female (mother). Standard Markers B D E F Mother Father hild hild Wells for injecting DN opyright lencoe/mcraw-hill, a division of he Mcraw-Hill ompanies, Inc. 148 HPER enetic echnology UNI 4