Antibiotics: The difference between prokaryotic and eukaryotic cells, Biology AA, Teacher Leslie Hadaway, New lesson, Science

Transcription

1 Antibiotics: The difference between prokaryotic and eukaryotic cells, Biology AA, Teacher Leslie Hadaway, New lesson, Science Antibiotics: The difference between prokaryotic and eukaryotic cells Author(s) Colleen McGannon and Leslie Hadaway Subjects Biology AA Grade level 10 Duration 1 54-minute class Rationale (How this relates to engineering and the STEMcinnnati theme) Students often have a difficult time remembering the differences between prokaryotic (bacterial) and eukaryotic (human) cells after the class is over. Antibiotics have been engineered to kill bacteria by targeting the features that are specific to the prokaryotic cells. In designing their own antibiotics, students will understand how the differences between the cells have played a role in their own health. In addition, many drug stores in Cincinnati have recently started to offer free antibiotics to patients. This fact allows for a closing discussion on antibiotic resistance and what role the free antibiotics may play in their daily lives. This lesson pertains to my research as I study the bacteria E. coli O157:H7, which produces a lethal toxin. As it has been shown that certain antibiotics increase toxin production by this bacterium, I am characterizing which antibiotics, if any, are safe for use. Activity Summary Students will be looking for information regarding free antibiotics at Cincinnati drug stores. The lesson will begin with a short discussion on the information they found. Students, as a class, will list the components of prokaryotic and

2 eukaryotic cells on the board. I will explain that the day s activity involves the creation of an antibiotic and go over the worksheet (see below). They will then be divided up into small groups where they will identify which prokaryotic cell feature would be a prime target for an antibiotic. The worksheet filled out will not be graded, but used by the students as a study guide. Activity Introduction: review of information found by students Review: students list cell components on the board Explanation of activity and the activity itself Discussion of results: relate their mechanisms back to specific antibiotics currently in use, talk about antibiotic resistance and free antibiotics Review of cell components and how the differences allowed for the creation of antibiotics Time 5 mins 5 mins mins 10 mins 4 mins Objectives Upon completion of this lesson, students will be able to: 1. Distinguish between the differences of prokaryotic and eukaryotic cells 2. List one antibiotic and describe its mechanism of action 3. Define antibiotic resistance 4. Discuss both sides of the debate regarding the distribution of free antibiotics by listing one pro and one con Standards Ohio Standard: Life Sciences Benchmark A: Explain that cells are the basic unit of structure and function of living organisms, that once life originated all cells come from pre-existing cells, and that there are a variety of cell types. Benchmark G: Describe how human activities can impact the status of natural systems.

3 Benchmark H: Describe a foundation of biological evolution as the change in gene frequency of a population over time. Explain the historical and current scientific developments, mechanisms and processes of biological evolution. Benchmark I: Explain how natural selection and other evolutionary mechanisms account for the unity and diversity of past and present life forms. Benchmark J: Summarize the historical development of scientific theories and ideas, and describe emerging issues in the study of life sciences. Ohio Standard: Science and Technology Benchmark A: Explain the ways in which the processes of technological design respond to the needs of society. Benchmark B: Explain that science and technology are interdependent; each drives the other. Ohio Standard: Scientific Inquiry Benchmark A: Participate in and apply the process of scientific investigation to create models and to design, conduct, evaluate and communicate the results of these investigations. Ohio Standard: Scientific Ways of Knowing Benchmark A: Explain that scientific knowledge must be based on evidence, be predictive, logical, subject to modification and limited to the natural world. Benchmark B: Explain how scientific inquiry is guided by knowledge, observations, ideas and questions. Benchmark D: Recognize that scientific literacy is part of being a knowledgeable citizen. Background knowledge Students will have learned the components of prokaryotic and eukaryotic cells and will have gathered information regarding the free distribution of antibiotics within Cincinnati. Materials Required Worksheet and the following websites: Free antibiotics in Cincinnati: Channel 5:

4 Channel 9: content_id=debdf2d8-3ed5-417d-a8fc-44c7b38bde21&gsa=true content_id=0de ccc-4bfd-a95e-7ea44359ebcc&gsa=true Antibiotic resistance: CDC web page: FDA web page: Article with diagrams: Activities Gaining attention: A week before the activity, the students will be informed that several stores throughout the country are starting to distribute free antibiotics with a prescription. They will have the task of finding a tangible piece of information regarding free antibiotics specifically within Cincinnati. Acceptable items include: newspaper articles, articles downloaded from the local news stations, a picture next to a sign in a drug store, a picture with a pharmacist etc. Stimulating the recall of prerequisite learning: The students will have learned the features of prokaryotic and eukaryotic cells previously. Students will be asked what those features are, and they will be listed on the board as the students respond. This will be changed according to what you specifically go over. I will also add a table with antibiotics that target the given mechanisms. Feature Prokaryotic Eukaryotic Size 0.2-2µm in diameter µm in diameter Nucleus No nucleus Nuclear membrane Organelles None Several Cell wall Composed of peptidoglycan Chemically simple if present Plasma membrane No carbohydrates or sterols Carbohydrates and sterols Ribosomes Small Large DNA Circular Linear

5 Informing learners of the objective: Students will be told that they will be designing their own antibiotics. Present the stimulus material: The students will be put into groups given a handout to complete. See below. Eliciting the desired behavior: Students will fill out the activity worksheet as they go and will be prepared to share the results with the class. Assessment of Student Learning Students will be given the quiz prior to learning about the cell. The 25 point quiz will be given to the students after the activity. 5 points will be given for the preactivity assignment of gathering information regarding free antibiotics in Cincinnati. The remaining 20 points will be on the quiz itself. Assessment of the Activity Distribution of the STEP activity assessment form.

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