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Scrolling clicker attendance See if you can figure out how to “click-in” on the scrolling screen to alert the computer that you are here.
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Front -> Back -> NAME (in BIG LETTERS) Career; What do you want to learn in this class?
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Thinking of what you want to get out of your college education and this course, which of the following is most important to you? a)Acquiring information (facts, principles, concepts) b)Learning how to use information and knowledge in new situations c)Developing lifelong learning skills
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Of these three goals, which one do you think you can make headway on outside of class by your own reading and studying? a)Acquiring information (facts, principles, concepts) b)Learning how to use information and knowledge in new situations c)Developing lifelong learning skills
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These goals are not achieved by reading or listening to a lecturer—you must actively do things in order to learn (Bio or Kung Fu) like
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When you discuss what you are reading When you practice what you are learning When you apply practices and ideas to new areas
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See different
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You are an intern
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PCR photocopies DNA
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Biological Information inter-species organismal communication in a population molecular communication
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Photographs of Pneumococcus Strains
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R strainS strain Photographs of Pneumococcus Strains
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R strainS strain Photographs of Pneumococcus Strains
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R strainS strain
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Photographs of Pneumococcus Strains R strainS strain lethalharmless
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Griffith’s Experiments
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Integrating Questions (set #1) 1. To help you think about what makes the S strain lethal and the R strain harmless, describe the differences you observe in Figure 1.2. What part of the cell do you think would be altered in order to change the overall appearance of the colony? 2. It is helpful to keep in mind the origin of a bacterial colony. What is the difference between a colony and a single cell? 3. Summarize the outcome of all four experiments in Figure 1.3. What conclusions can you draw from the final experiment involving both R and S cells? Can you use Griffith’s data to demonstrate that either DNA or protein is the heritable material?
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Bio-Math Exploration Integrating Questions 1.1a: Make a two-column table listing the number of possible DNA and protein sequences of length 5, 10, 20, 50 and 100. Put your answers in scientific notation so you can easily see how many digits are in each answer. 1.1b: Looking at the numbers in your table, can you see why Griffith and his contemporaries predicted that protein would be the heritable material?
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Integrating Questions (set #2) 4. Since the “S factor” was associated with the bacterial capsule, why couldn’t Griffith demonstrate that proteins are the heritable material? What type of experimental design would you like to see before being fully convinced of which kind of molecules contained the information that is passed from one generation to the next and defines each species? 5. To understand why washed capsules could no longer transform R cells into S cells, think about molecules that dissolve in water. Do fats dissolve in water? Bacterial chromosomes are made of DNA, they are loosely attached to the cell membrane, and they dissolve in cytoplasm. Speculate why washed capsules lost their transforming capacity.
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Genetic Material Determines Phenotype
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R strain S strain
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Genetic Material Determines Phenotype
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Integrating Questions (set #3) 6. Hypothesize what the white stringy material is in Figure 1.4a. (You may have performed a similar procedure during a lab at some point in your education.) If the cellular extract was clear before adding the ethanol, how did the white threads suddenly appear from nowhere? 7. At this stage, can you determine if the white substance is pure, or could it be a mixture of two or more types of molecules such as proteins and DNA?
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Avery’s Transforming Factor
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DNA and 4 samples had similar N composition
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Avery’s Transforming Factor DNA and 4 samples had similar P composition
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Avery’s Transforming Factor nitrogen/phosphorous ratios similar for 4 preparations and DNA
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Avery’s Transforming Factor
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Five Amino Acids
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peptide bonds
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Five Amino Acids amino acid backbones
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Five Amino Acids amino acid side chains
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Four Nucleotides
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4 phosphates
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Four Nucleotides 4 deoxyribose sugars
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Four Nucleotides 4 bases guanine = G cytosine = C adenine = A thymine = T
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Four Nucleotides
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Integrating Questions (set #4) 8. Table 1.1 highlights the nitrogen to phosphorous ratio (N/P) of the transforming material. Determine the N/P ratios for the five amino acids and four nucleotides shown in Figure 1.5. Why was the N/P ratio so important to Avery’s interpretation of their data? 9. Adding a protease to the S factor is a pretty good way to show proteins are not involved, but is this proof? Describe how a protein might not get inactivated when treated with these two proteases? Would the same consideration be true for RNA treated with RNase? 10. Perform a PubMed search using the phrase “Belanger Avery's” to find a 2004 paper that sheds new light on the pneumococcus strain R36A. PubMed is the “Google” of biomedical research papers. Read the abstract. What new information does this team from the drug company Eli Lilly uncover about the R colony morphology, or shape, seen in R36A?
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