Appendix C
Laboratory Experience in AP and IB Biology Courses

The AP manual (Educational Testing Service, 1999) suggests that “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 4—Plant Pigments and Photosynthesis

Lab 5—Cell Respiration

Lab 6—Molecular Biology

Lab 7—Genetics of Organisms

Lab 8—Population Genetics and Evolution

Lab 9—Transpiration System

Lab 10—Physiology of the Circulatory

Lab 11—Animal Behavior Primary

Lab 12—Dissolved Oxygen and Aquatic Production

The AP laboratories are not inquiry based and involve little instrumentation. The write-up varies from laboratory to laboratory and involves primarily 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 bacterial transformation using E. coli 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 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.



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Learning and Understanding: Improving Advanced Study of Mathematics and Science in U.S. High Schools - Report of the Content Panel for Biology Appendix C Laboratory Experience in AP and IB Biology Courses The AP manual (Educational Testing Service, 1999) suggests that “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 4—Plant Pigments and Photosynthesis Lab 5—Cell Respiration Lab 6—Molecular Biology Lab 7—Genetics of Organisms Lab 8—Population Genetics and Evolution Lab 9—Transpiration System Lab 10—Physiology of the Circulatory Lab 11—Animal Behavior Primary Lab 12—Dissolved Oxygen and Aquatic Production The AP laboratories are not inquiry based and involve little instrumentation. The write-up varies from laboratory to laboratory and involves primarily 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 bacterial transformation using E. coli 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 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.

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Learning and Understanding: Improving Advanced Study of Mathematics and Science in U.S. High Schools - Report of the Content Panel for Biology The IB program requires that 25 percent of the teaching hours “be spent following an internally assessed scheme of practical/investigative work, related to all aspects of the program including the options.” The subject and design of the labs is 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) Defined problem(s), research question(s); formulated hypothesis(es); selected any relevant variables. Planning (b) Designed realistic procedures to include appropriate apparatus, materials, methods for both the control of variables and collection of data. Data collection 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 result(s) of experiment(s) and evaluated procedure(s); suggested modifications to the procedure(s), where appropriate. A summative evaluation is done of the following three skills: Manipulative skills Carried out a range of techniques proficiently with due attention to safety; followed instructions. Personal skills (a) Worked within a team; recognized contributions of others; encouraged the contributions of others. Personal skills (b) 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, derived from the internal assessment by the teacher. The teacher grades both the Group 4 project (interdisciplinary investigation) and the labs, which together 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 compliance with the IBO internal assessment requirements. Portfolios from individual 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 components are Background Information, Question/Hypothesis,