High School INSIDE THE NUCLEUS: DNA. Teacher s Guide. Major Sponsor:

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1 High School Teacher s Guide INSIDE THE NUCLEUS: DNA Major Sponsor:

2 Introduction The Pritzker Laboratory for Molecular Systematics and Evolution at The Field Museum provides state-of-the-art molecular biology equipment for scientists to study the genetic diversity of life on earth. It is used by our curators, staff, students, and visiting scientists, who all contribute to our knowledge of the tree of life and how organisms, past and present, are related. As technology advances, so does our ability to analyze larger quantities of genetic data. Systems biology, the study of systems of biological components, is a growing and exciting field for your students to explore as a career pathway. Dr. Shannon Hackett is an Associate Curator in the Department of Zoology, and Head of The Field Museum s Bird Division. She studies the systematics and evolution of birds using DNA sequences, morphology, and behavior to reconstruct how populations and species are related to one another. As part of the Early Bird Project, Shannon, along with many other scientists, aims to resolve the evolutionary relationship between the major groups of birds. Shannon will share her expertise with your students to talk about how scientists use DNA to understand the relationship on life on Earth and how they can prepare for a career in systems biology. Erica Zahnle is The Field Museum s DNA Educator and Researcher. Erica splits her time between conducting research in the Pritzker Lab and teaching students and teachers about research happening at the Museum. Each summer, Erica runs the DNA Residency program for high school students and teachers. She trains them to conduct molecular systematics research, which they present at the end of the summer. Teachers create standards-aligned lessons based on their research experience, which are available online at fieldmuseum.org/educators/resources/systems-biology and can be used to supplement your Virtual Visit from The Field experience. Erica will talk to your students about the research she has conducted at the Museum and how they can get involve with systems biology as a high school student. Background Adapted from the DNA Discovery Center Educator Guide All living things are made of cells. Each cell contains genetic instructions stored in a molecule called deoxyribonucleic acid (DNA), and is found in the nucleus of eukaryotes. DNA is the substance of genes, the units of inheritance that transmit information from a blueprint T1

3 for building different parts of the cell. For example, an optical cell uses DNA that specifies the structure and function of the eye; where as a cardiac cell uses DNA that contributes to heart functions. Therefore, during development, a cell reads only the part of the DNA that it needs. Each DNA molecule forms a chromosome that contains regions called genes, which guides the production of one particular component of an organism. A set of human chromosomes contains one copy of each of the 30,000 genes in the human genome. Genes provide the instructions for producing all the biological components of organisms. Genes govern metabolic processes, as well as specifying physical characteristics. Traits such as an individual s height or skin tone require the actions of many genes working together. Humans share 100% of the same genes, it is the actual nucleotide sequences that make up any individual organism s genome that are not entirely identical. Although the DNA of any two people on earth is 99.5% identical, it is the little differences that can have a big effect on how the genes are expressed. The DNA molecule comes in the form of a twisted ladder shape called a double helix. The ladder s rungs are built with the four nucleotides: adenine (A), thymine (T), guanine (G), and cytosine (C). These four nucleotides are all that s needed to write a code that describes an entire organism s body plan. These instructions are read as a string of A s, C s, G s, and T s, which code for production of various proteins. How do scientists obtain the DNA of the organisms they are studying? More importantly, what do they do with the information once they have it? Inside the DNA lab at The Field Museum, there are numerous projects going on. Some scientists have traveled to the rainforests of South America to study bats, while others have focused their attention on lichens from Sweden. In both cases, these scientists collect the DNA of their target species, analyze the DNA, and use this analysis to understand which species are related, how species evolved, and how particular species fit into overarching trees of life. Scientists have done this analysis in the past using the physical traits of organisms as the primary mean of classification, among other techniques. But now, DNA analysis allows scientists to map relatedness among species at the molecular level, often resulting in dramatic changes in how we previously had classified organisms. T2

4 Activity 1 BROADCAST After this lesson your students will be able to: Explain how DNA is used to provide evidence of evolution. Describe the processes scientists use to obtain and analyze DNA from an organism. Identify careers in systems biology. MAIN IDEAS Genetic information provides evidence of evolution. There is genetic diversity among organisms, but overlap in DNA of different species can be used to infer evolutionary relationships and diversity. Broadly, there are four steps in obtaining genetic information from an organism: 1) Collect a biological sample; 2) Extract DNA ; 3) Amplify 4) Analyze. MATERIALS AND PREP It is recommended that you do the following prior to this lesson: Read the Virtual Visits Technical Guide Attend the webinar test-run, link and direction will be provided one week prior to your Visit Check with your IT specialist to make sure you will have available bandwidth on the day of your Visit You will need the following materials: Computer connected to the Internet Projector Optional: Scrap paper or note cards PREREQUISITE KNOWLEDGE DNA contains instructions for biological structures and functions. Genetic information is passed from parent to offspring, from generation to generation. T3

5 NGSS Alignment Thanks to the DNA Residency for Educators program, you can accompany your Visit with a variety of teacher-created curriculum based on Museum research conducted in the Pritzker DNA Discovery Center. Below, you will find a roadmap that aligns each lesson to the Next Generation Science Standards or Common Core State Standards for Science & Technical Subjects. Lesson plans and supplemental materials for these activities can be accessed from: The Case of Darwin s Finches HS-LS4-1. Communicate scientific information that common ancestry and biological evolution are supported by multiple lines of empirical evidence. Crosscutting Concepts HS-LS4-5. Evaluate the evidence supporting claims that changes in environmental conditions may result in: (1) increases in the number of individuals of some species, (2) the emergence of new species over time, and (3) the extinction of other species. The Case of Gene Regulation in Cells HS-LS1-1. Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells. HS-LS1-2. Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms. The Effect of Natural Selection on Genes, Traits, and Individuals HS-LS3-3. Apply concepts of statistics and probability to explain the variation and distribution of expressed traits in a population. HS-LS4-4. Construct an explanation based on evidence for how natural selection leads to adaptation of populations. HS-LS4-5. Evaluate the evidence supporting claims that changes in environmental conditions may result in: (1) increases in the number of individuals of some species, (2) the emergence of new species over time, and (3) the extinction of other species. T4

6 The Case of the Mystery Fish Toxin CCSS.ELA-Literacy.RST Follow precisely a complex multistep procedure when carrying out experiments, taking measurements, or performing technical tasks, attending to special cases or exceptions defined in the text. CCSS.ELA-Literacy.SL Present information, findings, and supporting evidence clearly, concisely, and logically such that listeners can follow the line of reasoning and the organization, development, substance, and style are appropriate to purpose, audience, and task. CCSS.ELA-Literacy.WHST Conduct short as well as more sustained research projects to answer a question (including a self-generated question) or solve a problem; narrow or broaden the inquiry when appropriate; synthesize multiple sources on the subject, demonstrating understanding of the subject under investigation. T5