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Biotechnology Applying the Genetic Revolution

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Biotechnology Applying the Genetic Revolution Biotechnology Applying the Genetic Revolution Chapter 1: Basics of Biotechnology 1. Which statement best describes the central dogma of genetics? a. Genes are made of DNA, expressed as an RNA intermediary that is decoded to make proteins. b. The central dogma only applies to yellow and green peas from Mendel’s experiments. c. Genes are made of RNA, expressed as a DNA intermediary, which is decoded to make proteins. d. Genes made of DNA are directly decoded to make proteins. e. The central dogma only applies to animals. 2. What is the difference between DNA and RNA? a. DNA contains a phosphate group, but RNA does not. b. Both DNA and RNA contain a sugar, but only DNA has a pentose. c. The sugar ring in RNA has an extra hydroxyl group that is missing in the pentose of DNA. d. DNA consists of five different nitrogenous bases, but RNA only contains four different bases. e. RNA only contains pyrimidines and DNA only contains purines. 3. Which of the following statements about eukaryotic DNA packaging is true? a. The process involves DNA gyrase and topoisomerase I. b. All of the DNA in eukaryotes can fit inside of the nucleosome without being packaged. c. Chromatin is only used by prokaryotes and is not necessary for eukaryotic DNA packaging. d. Eukaryotic DNA packaging is a complex of DNA wrapped around proteins called histones, and further coiled into a 30-nanometer fiber. e. Once eukaryotic DNA is packaged, the genes on the DNA can never again be expressed. 4. Which statement about Thermus aquaticus is false? a. T. aquaticus was isolated from a hot spring. b. The DNA polymerase from T. aquaticus is used in molecular biology for a procedure called polymerase chain reaction (PCR). c. The DNA polymerase from T. aquaticus is able to withstand very high temperatures. d. T. aquaticus can survive high temperatures and low pH. e. T. aquaticus is found in the frozen lakes of Antarctica. 5. Which statement about Escherichia coli is not correct? a. E. coli is called “the workhorse of molecular biology.” b. E. coli can grow in a simple solution of water, a carbon source, and mineral salts. c. All E. coli strains are pathogenic, and therefore must be handled accordingly. d. The chromosome of E. coli consists of one circular DNA molecular containing approximately 4000 genes. e. All of the above answers are correct. 6. Plasmids from bacteria can be described by which of the following statements? a. Plasmids provide an advantage to the host bacterium to compete against non-plasmid-containing bacteria for nutrients. b. Plasmids are used as a molecular biology tool to express other genes efficiently in the host bacterium. c. Plasmids are extrachromosomal segments of DNA that carry several genes beneficial to the host organism. d. Plasmids have their own origin of replication. e. All of the above statements describe plasmids. 7. Which of the following statements is not correct about the usefulness of fungi in biotechnology research? a. Fungi produce the blue veins in some types of cheeses. b. Yeast is responsible for the alcohol in beer and for bread rising. c. Fungi are called “the workhorses of molecular biology.” d. The 2-micron circle is a useful extrachromosomal element from yeast that can be utilized in molecular biology research. e. Fungi produce many industrial chemicals and pharmaceuticals. 8. What mechanism does yeast utilize to control mating type in the cells? a. Yeast is only able to reproduce through mitosis. b. The MAT locus in the yeast genome contains two divergent genes that encode for the pheromones a and α, along with the pheromone receptors. c. The mating type of yeast is determined by pheromones called b and β. d. There are no mechanisms to control mating type in yeast because all of the cells are structurally the same. e. Yeast mating types are generally referred to as either male or female. 9. Which of the following yeast cellular component is typically not found in bacteria? a. centromeres b. telomeres c. nuclear pores d. nuclear envelope e. All of the above are found in yeast and not bacteria. 10. Identify the statement about multicellular model organisms that is correct. a. C. elegans has been used extensively to study multicellular interactions partly because the creature can reproduce by self-fertilization (genetic clones) or sexually (novel genetic organisms). b. Based on homology, research on Drosophila mutants has identified genes in the human genome responsible for body patterns. c. The zebrafish, or Danio rerio, are used to study developmental genetics because the embryonic cells are easily destroyed or manipulated and the effects can be observed within 24 hours. d. The mouse is a model organism for studying human genetics, physiology, and development because less than 1% of the genes in the mouse genome have no genetic homology in humans. e. All of the statements are correct. 11. What is the main advantage for studying cells in culture rather than in a whole organism? a. Cell lines in culture are easily manipulated genetically to introduce new genes or delete other genes. b. Cell lines are not very stable and therefore, it is more advantageous to study cells within the organism itself. c. There is no advantage to studying cells in a cell line rather than in a live organism. d. The information obtained from studying cell lines as opposed to live organisms is not relevant to what happens in vivo. e. None of the above is the main advantage. 12. Why is Arabidopsis thaliana used as a model organism for plant genetics and biology? a. Arabidopsis responds to stress and disease similarly to important crop plants such as rice, wheat, and corn. b. Arabidopsis is easy to grow and maintain in the laboratory. c. The genome of Arabidopsis is relatively small compared to other plants. d. The generation cycle of Arabidopsis is shorter than most other crop plants and produces many seeds for further study. e. All of the above statements are reasons for using Arabidopsis as a model organism. 13. Why are viruses significant to biotechnology? a. They are able to insert their genome into the host genome, thus integrating genes in the process. b. Viruses can be used to alter the genomes of other organisms. c. Reverse transcriptase, an enzyme used in molecular biology, is encoded in a retroviral genome. d. Viruses play an important role in delivering gene therapy to humans. e. All of the above statements are reasons why viruses are significant to biotechnology research. 14. Which statement best describes the F plasmid? a. F plasmids contain genes for formation of a specialized pilus that forms a conjugation bridge between two cells for the purpose of transferring genetic material. b. The F plasmid does not have an origin of replication and can therefore not replicate itself. c. The primary host for the F plasmid is Saccharomyces cerevisiae. d. The F plasmid is not important for biotechnology research. e. All of the above statements describe the F plasmid. 15. Which of the following elements is important in biotechnology research? a. transposons b. F plasmid c. satellite viruses d. plasmids e. all of the above Answer Key CHAPTER 1 1:A, 2:C, 3:D, 4:E, 5:C, 6:E, 7:C, 8:B, 9:E, 10:E, 11:A, 12:E, 13:E, 14:A, 15:E Biotechnology Applying the Genetic Revolution Chapter 2: DNA, RNA and Protein 1. Which of the following are important features for transcription? a. promoter b. RNA polymerase c. 5′and 3′UTRs d. ORF e. all of the above 2. For which of the following nitrogenous bases does DNA substitute thymine? a. uracil b. adenine c. guanine d. cytosine e. inosine 3. Which of the following is not necessary during Rho-independent termination of transcription? a. RNA polymerase b. Rho protein c. hairpin structure d. repeating A’s in the DNA sequence e. All of the above are necessary. 4. Which of the following statements is not true about mRNA? a. Prokaryotic mRNA may contain multiple structural genes on the same transcript, known as polycistronic mRNA. b. Eukaryotes only transcribe one gene at a time on mRNA, called monocistronic mRNA. c. Eukaryotes are capable of having polycistronic mRNA; however, only the first cistron will be translated. d. Eukaryotes almost always produce polycistronic mRNA. e. The genes for metabolic pathways in bacteria are typically located close together and transcribed on one mRNA. 5. In what way is eukaryotic transcription more complex than prokaryotic transcription? a. Eukaryotes have three different RNA polymerases, whereas prokaryotes only have one RNA polymerase. b. Eukaryotic transcription initiation is much more complex than prokaryotic initiation because of the various transcription factors involved. c. Upstream elements are required for efficient transcription in eukaryotic cells, but these elements are not usually necessary in prokaryotes. d. Eukaryotic mRNA is made in the nucleus. e. All of the above statements outline ways that eukaryotic transcription is more complex. 6. Why is the lac operon of E. coli important to biotechnology research? a. IPTG is a cheaper additive than lactose to growing cultures. b. The lac operon is not used in biotechnology research. c. The inducers and regulators of the lac operon are used to control the expression of genes in model organisms. d. The lac operon controls the amount of lactose that E. coli metabolizes. e. All of the above. 7. What feature about eukaryotic transcription factors is useful to biotechnology research? a. They have two domains, both of which bind to DNA. b. They have two domains, both of which bind to separate proteins.
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