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331 AN panels D Laboratory Experience in AP and IS Biology Courses The AP manual (Educational Testing Service, 1999) suggests "since one- fourth to one-third of the credit in comparable college courses is derived from laboratory work, AP courses should likewise emphasize laboratory work." There are 12 recommended laboratory exercises: Lab 1 Diffusion and Osmosis Lab 2 Enzyme Catalysis Lab 3- Mitosis and Meiosis Lab 4Plant Pigments and Photosynthesis Lab 5Cell Respiration Lab 6 Molecular Biology Lab 7 Genetics of Organisms Lab Population Genetics and Evolution Lab 9 Transpiration Lab 10 Physiology of the Circulatory System Lab 11 Animal Behavior Lab 12 Dissolved Oxygen and Aquatic Primary Production The AP laboratories are not inquiry based and involve little instrumenta- tion. The write-up varies from laboratory to laboratory and involves prima- rily filling in the data table and/or blanks along with providing some "short" extended responses. There is no external check on whether the laboratories are completed. An example is AP Lab 6, Molecular Biology. Lab 6a demonstrates bacte- rial transformation using E. cold and the pAMP plasmid. Students are given a step-by-step procedure. The analysis consists of four questions: #1 is a cell count; #2 is a comparison; #3 leads students through a calculation of the transformation efficiency; and #4 is open ended and asks students to discuss factors influencing transformation efficiency. Lab 6b is called "Restriction Enzyme Cleavage of DNA and Electrophoresis." Students are told to conduct

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332 . CONTENT PANEL REPORT the lab following directions provided either by their teacher or by the kit they are using. Students do not perform their own digest; they merely load DNA that has been digested for them. They are provided with a photo of a gel carrying size markers and asked to represent graphically the relationship between migration rate and fragment length. They then analyze their own gels to determine the size of their fragments by measuring the migration rates. The IB program requires that 25 percent of the teaching hours "be spent following an internally assessed scheme of practical/investigative work, re- lated to all aspects of the program including the options." The subject and design of the labs are at the teacher's discretion. These are used to create a portfolio and must be written using a specified format. The "criteria" are as follows: Planning (a) Planning (b) Data collection Defined problemVs), research questionts); formulated hypothesiskes); selected any relevant variables. Designed realistic procedures to include appropriate apparatus, materials, methods for both the control of variables and collection of data. Observed and recorded raw data with precision and presented them in an organized way (using a range of appropriate scientific methods/techniques). Data analysis Transformed, manipulated and presented data (in a variety of appropriate ways) to provide effective communication. Evaluation Evaluated the resultts) of experimentVs) and evalu- ated procedurets); suggested modifications to the procedurefs), where appropriate. A summative evaluation is done of the following three skills: Manipulative skills Personal skills (a) Personal skills (b) Carried out a range of techniques proficiently with due attention to safety; followed instructions. Worked within a team; recognized contributions of others; encouraged the contributions of others. Approached experiments/investigations/projects and problem-solving exercises with self-motivation and perseverance and in an ethical manner; paid due attention to the environmental impact. The portfolio accounts for 24 percent of the student's final grade, de- rived from the internal assessment by the teacher. The teacher grades both

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BIOLOGY the Group 4 project (interdisciplinary investigation) and the labs, which to- gether constitute the portfolio. IB teachers are required to submit a description ("practical scheme of work") of laboratory work done in their class to an external examiner. The examiner moderates the overall practical scheme of work experienced by the students and provides feedback to teachers and schools on their compli- ance with the IBO internal assessment requirements. Portfolios from indi- vidual students are sampled by the examiners to enhance standardization of grades across the program. There is no laboratory in the IB program that is directly comparable to the above AP example. Teachers may select any molecular genetic activities they wish. However, teachers are provided with an "inquiry template" that specifies what components a laboratory should include. Recommended com- ponents are Background Information, Question/Hypothesis, Design/Proce- dure, Data Collection, Data Analysis, Evaluation, and Manipulative and Per- sonal Skills. Students are charged to work collaboratively but with individual accountability and to pay attention to the ethical and environmental implica- tions of the investigation. Not all laboratories must include all the above components, but each component must be assessed twice during the course (and teachers are encouraged to "address" each component multiple times). 333