Name: Period: Date: AP Bio Module 6: Bacterial Genetics and Operons, Student Learning Guide Getting started. Work in pairs (share a computer). Make sure that you log in for the first quiz so that you get credit. 3. Go to www.sciencemusicvideos.com Select the AP Biology Menu. Then select Module 6: Bacterial Genetic Diversity and Bacterial Gene Regulation (Operons). Start with Sources of Genetic Diversity in Bacteria. Tutorial. Sources of Genetic Diversity in Bacteria. Read. Shouldn t all the bacteria of the same species be clones? Check this box when you re finished. CHECKING UNDERSTANDING: Why, based on how bacteria reproduce, would you expect all bacteria of the same species be clones? Explain briefly how the two forms of transformation are different. Make a key to the diagram below. Identify each labeled part, and write a short description of each numbered step.. Make a key to the diagrams below. Same instructions as for the previous diagram. a a. 3. 4. 5. 6. A. b c 2 3 b.. B C. D. E. 2c. Read about bacterial conjugation. Make a key to the diagram below. Note that there s no letter d a. b. 2a. Read about Mutation. 2b. Read about transformation, starting with the one question quiz showing Frederick Griffith s demonstration of the transforming factor in pneumonia causing bacteria. Write your own explanation in the space below, then adjust your answer as needed after clicking Show me the answer. You can continue your answer on the top of the next column. : 2: 3: c. e. www.sciencemusicvideos.com Page of 5
4: 2d. Transduction We learned about transduction in the previous unit. See if you make a key for the diagram below. If you re having difficulty, go back and review the material in module 5 and complete the key. 4: 5: Now make a key for this one:. 3. 4. 5. 6. a b c d e f g 2 3 4 5 3. Take the Bacterial Genetic Diversity: Checking Understanding Quiz SYNTHESIZING WHAT YOU VE LEARNED A student taking 9 th grade biology says to you aren t all bacterial clones? Tell them what you know about the sources of diversity in bacteria. Write small. 7. 2e. Read the section about transposition, and study the associated diagrams. REFLECT: How are transposons similar to viruses? How are they different? Make a key for the diagram below. Click the link to Operons, the next tutorial Tutorial 2: Operons. If it s useful, click through the slides. Read the introduction, and, in the space below, use what you know about natural selection to explain why control of gene expression is of great survival value. : 2: 3: www.sciencemusicvideos.com Page 2 of 5
3. Read Operons: Description and Definition. 4. Read The Lac Operon 5. Complete the Lac Operon: Labeled Diagrams Explain it. The diagram below shows the lac operon when lactose is absent. And this shows the tryp operon in the absence of tryptophan. This diagram shows the operon when lactose is present In the space below, write a paragraph explaining how the tryp operon works. Again, make sure you explain each numbered part of the diagram. In the space below, write a paragraph that explains how the lac operon works. As you do, make sure that you explain each numbered part in the diagram. 9. Read about CAP, stopping at the horizontal line. SPECULATE: What s happening in the single food (glucose only) E. coli growth curve on the right? Why is there a lag in growth when E. coli is fed two foods (such as glucose and lactose?) 6. Read The Tryp Operon 7. Complete the Tryp Operon: Labeled Diagrams 8. Take the Operons Quiz Explain it The diagram below shows the tryp operon in the presence of tryptophan Fill the space below with your speculations. www.sciencemusicvideos.com Page 3 of 5
Read the rest of the passage explaining how CAP works. YOU EXPLAIN IT Here s the CAP system when glucose and lactose are present: And here s the system when glucose is scarce and lactose levels are high. Explain how this system enable an E. coli cell to choose glucose over lactose when both are available, and then to turn to lactose only when glucose supplies are scarce. www.sciencemusicvideos.com Page 4 of 5
sciencemusicvideos AP Biology Name: Bacterial Genetics and Operons 2 3 5 6 7 8 4 9 0 2 3 4 5 6 9 2 7 20 22 8 Across: 2 - Picking up DNA in the environment 5 - A disaccharide that is found in milk. 7 - This type of AMP is produced by the cell when glucose is in short supply. 9 - "In an operon, these are the genes that code for enzymes." - A DNA element that can move from one position in the genome to another 2 - A DNA region just "downstream" of the promoter, where regulatory proteins can bind. 4 - Both the trp and lac operons involve regulation (through repressors). 5 - Operons only work because regulatory proteins are subject to regulation. 7 - random change in DNA 8 - The area where RNA polymerase binds. 9 - The amino acid that is the regulated product of the trp operon. 20 - These genes produces regulatory proteins, which control transcription 2 - E. coli reproduces though binary 22 - An extra-chromosomal circle of DNA Down: - The lac operon is an system (think about what lactose does) 3 - The enzyme reverse is required in the retrotransposon life cycle. 4 - A DNA element that must make itself into RNA before sending a DNA copy of itself to another location in the genome 6 - Operons are mostly about control of of related genes. 8 - E. coli's home 0 - The trp operon is a system (think about what tryptophan does) - Gene transfer that occurs when viruses carry bacterial DNA from one cell to another 3 - When one bacterial cell passes a copy of its plasmid to another. 6 - A cluster of genes under the control of a single promoter. 8 - A cellular extension used during conjugation. www.sciencemusicvideos.com Page 5 of 5