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161 Multiple Applications for Computers in Biochemical Education R P LEARMONTH, B G LIVETT, W H SAWYER and S P JONES

The Russell Grimwade School of Biochemistry University of Melbourne Parkville, Victoria 3052, Australia Introduction The Department of Biochemistry, University of Melbourne, teaches students from the faculties of Science, Agricultural Science, Dental Science and Medicine. Computers are used for tutorial-style presentations, simulation of biochemical reactions, experimental data acquisition and analysis, and for information management. Several approaches to computer-aided learning (CAL) have been incorporated into various courses, the objectives and level of each course determining the nature of computer use, ranging from 'drill and practice' to the use of sophisticated research-oriented systems. Differences in Objectives Between Medicine and Science Courses An example of the different objectives of courses is provided by a comparison of the Medicine and Science courses. These courses have both common and conflicting requirements and objectives. For medical students, the development of skills associated with practical laboratory work is less important than the assimilation and understanding of theoretical concepts and the ability to interpret experimental data. In a hospital, trained laboratory staff usually perform clinical biochemistry tests, but it is the doctor who must understand the biochemical and physiological basis of a test and who must interpret the result. Part of the practical component of the medical course is therefore being replaced by microcomputer-based simulations and tutorial exercises. Simulation programs allow students to gather and analyse experimental data that it would be impossible to acquire in the course of a laboratory class. Tutorialtype programs are used to present and emphasise theoretical concepts, and are integrated with other sources of information such as textbooks, lecture notes and tutorial staff. In contrast, the development of laboratory skills is essential for science students, and CAL is used as a supplement rather than a replacement of traditional teaching methods. The science curriculum includes computer-based tutorials and simulations, computer-controlled acquisition and analysis of experimental data, and the use of programs for information management in research (eg DNA sequence analyses). CAL in the Medical Course The traditional course in biochemistry for medical students has consisted of a theoretical component (lectures) and a practical component (laboratory work). As a result of discussions with students, and in response to BIOCHEMICAL E D U C A T I O N 16(3) 1988

faculty initiatives, a major reorganisation of the course was undertaken, including re-evaluation of the course objectives. It was felt that tutorial classes should receive more emphasis. However, due to the large number of students (a total of approximately 400 in years II and III), this would necessitate an expanded timetable and the employment of more tutors. Other possibilities for filling the 'tutorial gap' were considered including the use of audiovisual aids (tape/slide tutorials), video presentations, and computer-aided instruction. These methods have the advantage that students can control their own pace of learning. Moreover, some standardisation of tutorials can be achieved thereby eliminating variation in the approaches of different instructors. Another objective was to reduce the emphasis on the acquisition of manipulative skills in the practical component of the medical course, and to increase the emphasis on the theoretical concepts underlying the experimental procedures. The practical component was not completely replaced, since it remains important for medical students to appreciate general laboratory procedures and practices, the sources of errors involved in laboratory tests, and the technology and human factors which must be considered. To date, computer-aided instruction has been used to reinforce information provided in introductory talks of practical classes. In addition, two laboratory sessions have been replaced by 'Practice Classes', which include microcomputer-based simulations and data analysis exercises within the framework of the traditional tutorial session. The laboratory becomes a general workplace with students moving between hands-on bench work, demonstrations and the computer laboratory, as need demands. A small computer laboratory has been set up adjacent to the teaching laboratory. Six IBM-JX microcomputers with colour graphics capability are used for the presentation of tutorial material. These student workstations are connected via a local area network to an IBM-AT microcomputer which acts as a central file-server and stores all programs and data for student use. Tutorial Exercises Lessons have been presented to science and medicine students using the 'Q' instruction program, x The format of the lessons includes presentation by the microcomputer of textual and diagrammatic information, combined with multiple-choice questions. Students are also referred to other sources of information such as textbooks, lecture notes, and tutorial staff. The tutorial programs deal with aspects of basic biochemistry and carbohydrate metabolism, and reinforce the learning of established facts and theoretical concepts. Simulation Computer simulations of biological reactions have been applied in this department over a number of years. 2-4 Medical students are presented with a program that simulates an enzyme-catalysed reaction ('ENZ'). The

162 program allows students to manipulate experimental reaction conditions such as time, temperature, pH, and the concentrations of enzyme, substrate or inhibitor, to determine the effect on the enzyme reaction. Enzyme catalysis is measured by product accumulation. Data may be graphed on the computer, and students can collect data for the calculation of Vmax and Km. This simulation replaced a series of complicated and lengthy experiments. Once the skills of carrying out an enzyme assay had been mastered, the experiments became repetitious and tedious to the extent that the learning process was compromised. Simulated experimental data can rapidly be generated and analysed, and computer graphics can be used to present the results. The emphasis is effectively moved from the development of manipulative skills required to obtain the raw experimental data to the analysis and interpretation of the data. More complex simulations of biochemical equilibria have been used by final year Science students. The programs simulate reactions that are extremely difficult or impossible for students to perform using available equipment (eg rapid reaction kinetics to monitor changes in the concentrations of reaction intermediates). These programs are presented to the students as part of organised tutorials associated with the practical course. Students typically spend a full day using each program. The programs include RATES which simulates MichaelisMenten enzyme kinetics, and HB which simulates the binding of oxygen to haemoglobin. In the RATES program students can vary the rate constants for the individual reactions: E+S

K, ~_5 E-S ---, E + P K2 K3

Starting conditions are set by specifying the total concentrations of enzyme and substrate. Simultaneous differential equations are solved numerically to determine the concentrations of products and reactants as a function of time. Students are required to determine the effects of rate constants and enzyme and substrate levels on the steady state condition, and are asked to discuss whether such conditions exist in vivo. The HB program allows students to study allosteric mechanisms by modelling the haemoglobin-oxygen system. Equilibrium constants for the four oxygen binding sites of haemoglobin are specified, and binding curves are generated and presented graphically. Manipulation of the equilibrium constants provides information on the cooperativity of the multiple binding sites under various conditions. The program serves as an introduction to more general treatments involving the binding of ligands to allosteric or nonequivalent sites on a macromolecular acceptor. The simulation programs allow students to apply their knowledge of theory to formulate hypotheses which may be tested by altering the conditions of the experimental models. Analysis of the resultant data aids a clearer

B I O C H E M I C A L E D U C A T I O N 16(3) 1988

understanding of the mechanisms involved in the control of metabolism.

Revision Exercises Tutorials based on various lecture courses have been made available to students out of class hours. In addition, revision quizes have been made available at the end of term. These exercises allow students to evaluate their understanding of particular subjects prior to examinations. A novel approach to the generation of CAL is to invite students to create tutorials and revision material for their own peer group. To this end, a total of fifteen third-year medical students have participated over the last four years in an Advanced Study Unit (ASU) called 'Design and Evaluation of Computer-Aided Instruction in Metabolism and Endocrinology'. The unit was linked to the corresponding lecture unit on Metabolism and Endocrinology taken by all third-year medical students. The ASU students were encouraged to concentrate on the more difficult aspects of the lecture course. The development of each student's tutorial was continually monitored, and revisions of subject content were suggested as appropriate. The resultant tutorials are of high quality and contain some original and entertaining text. The students' interest in the area was stimulated and their knowledge of the chosen topic was improved. The curiosity factor encouraged otherwise reluctant students to try out the CAL tutorials that their peers had developed. Evaluation of Computer-Based Tutorials and Simulations The practice classes and revision exercises have been accepted with enthusiasm by the majority of students. In part this is due to the novelty of using a new technology. The introduction of practice classes has generally increased the medical students' basic understanding of practical biochemistry, including the ability to evaluate data obtained from various clinical tests. Another advantage is the elimination of some of the laboratory work which many medical students and staff see as irrelevant to their training as practitioners. The revision exercises are seen by the students as a valuable aid for reviewing lecture material in preparation for examinations. It has been noted that students who studied the ASU revision lessons described above have tended to perform better than average in the Metabolism and Endocrinology examination. A more formal evaluation of the effectiveness of computer simulation was undertaken by McDougal, Sawyer and Ciesielski,3 vcho found that students showed a significant increase in achievement test scores after taking the computer exercises. In the early stages of development of the CAL programs there was a tendency to include too much text on screen. We have since followed guidelines for the production of CAL material that are now widely accepted. These guidelines include the presentation of concepts and facts in a logical, ordered sequence, with the introduction of only one concept in a lesson screen or

163 module. The layout of the screens must be uniform, with a minimum of text, and where appropriate graphical information, diagrams or flowcharts should be included. Reference may be made to additional material such as tutorial notes or textbooks, especially for complex tabular information or pictorial material, or to visual material such as molecular models. Questions may be used effectively to probe student knowledge of a new topic, to test the assimilation of knowledge, and to re-inforce important points of previously presented material.

Computer-Aided Data Acquisition and Analysis Since computer controlled equipment is now commonplace in professional biochemistry laboratories, it was felt desirable to investigate the introduction of this technology into undergraduate laboratory classes. A microcomputer was evaluated as an "intelligent" replacement for an analogue chart recorder. The microcomputer and associated analogue-to-digital signal converting hardware was used for data capture and manipulation in an experiment which involved the investigation of oxidative phosphorylation by mitochondria. 5 The analytical equipment consisted of a polarographic oxygen sensitive electrode used to measure the rate of oxygen consumption by mitochondria in a reaction vessel. The oxygen level in the reaction vessel, traditionally represented by a chart-recorder trace, was displayed as a trace across the microcomputer screen. Diagrams outlining data acquisition by chart-recorder and computer-based systems are presented in Figs 1 and 2, respectively. One of the main benefits of using a computer for this purpose is the elimination of tedious, repetitive calculations, with an added improvement in the accuracy and objectivity of data manipulation. For example, analysis of data from a chart recorder may involve considerable error INSTRUMENT

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BIOCHEMICAL EDUCATION 16(3) 1988

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Figure 2 Data acquisition, analysis and storage using a microcomputer-based system in the measurement of the slope of a line by ruler. Often the calculations are complicated and time-consuming and therefore susceptible to errors. In contrast, the microcomputer can use averaging and curve-fitting procedures and produce a printed summary of the data as well as a copy of the plotted data. The computer allows the introduction of linear and non-linear least-squares fitting procedures with some discussion of the pitfalls in their use. Points for analysis of the raw data can be specified with high resolution by using moveable cursor lines on the computer screen. Data storage is improved significantly since the data may be stored on a computer disc and copied with no degradation in quality. Such degradation and some distortion is invariably experienced in the older process of photocopying paper traces. Students generally preferred to use computer-based rather than analogue-based equipment. The facilities provided by the computer allow them to streamline their experimental procedures and to remove the bottleneck often encountered in data manipulation and analysis. When used as a data-capture device, a microcomputer has been found to be particularly useful for expanding the scope of the laboratory equipment. The function of the apparatus has been increased from that of a simple recording instrument to one capable of complicated analysis and storage of data, and in addition presentation of instructional tutorials. Identification of the limitations of the Apple lie microcomputer used in the development project necessitated the further assessment of the type of computer equipment that would be the best suited to our requirements. Future plans include upgrading the data acquisition system to run on the IBM-JX microcomputer network, using analogue-to-digital conversion hardware developed in the Department of Physics, University of Melbourne. Interfaces will be developed to other labora-

164 tory equipment such as spectrophotometers and microtitre plate readers. Tutorials on the operation of the equipment as well as on theoretical aspects of the practical classes will be presented with the upgraded data analysis system.

Application of Software for Research Third- and fourth-year science students are given assignments relating to the use of research-oriented computer programs. These programs are used by various groups in the department and include software for the analysis of DNA sequences and of biochemical equilibria and kinetics. The programs act on real data from experiments, eg fitting experimental data to theoretically expected functions. Thus the students are provided with problems which they might experience in their careers as professional scientists. Use of Utility Software There is a growing use of 'utility' software by fourth-year students, postgraduate students and staff within the department. Wordprocessing software is used to prepare reports, publications and theses, and microcomputers are being used increasingly to prepare graphics and figures for inclusion in poster presentations and publications. As well as the special-purpose programs mentioned above, databases and spreadsheets are used to manipulate and store experimental data. Computerized information retrieval systems for literature surveys are also utilized - - these searches are usually performed by library staff working in association with the biochemist. In addition, personal literature retrieval systems such as 'Ref-ll', 'Cardbox' and 'Reference Update' are proving useful. Computer-Managed Learning Wordprocessing software is used extensively in the preparation of class notes. Increasing use is being made of spreadsheets for the management of practical class and examination marks. Spreadsheets have been set up to collate student attendances and marks, to combine the raw results and to calculate final grades. This allows rapid completion of a vast number of manipulations that in the past had constituted a tedious and error-prone manual task. The spreadsheets have also been used to assist in preparation of class summaries, for example class lists ranked in order of academic performance. The use of spreadsheets for the production of frequency distributions of marks for different examination questions and examiners has facilitated the evaluation of our teaching strategies. Further Developments Our aims for future development of tutorial CAL include progressive replacement of the practical component of the medical course in biochemistry and the introduction of more revision material to eventually cover the entire lecture course. These developments in the medical course have application to other courses taught by the departBIOCHEMICAL EDUCATION 16(3) 1988

ment. We are presently developing basic core material relevant to all of these streams, with more specialised tutorials to follow for each individual course. The use of interactive videodisc technology will also play a significant role in CAL. However, its full introduction into our teaching programs is some years in the future. A project is currently underway to create an interactive videodisc-based encyclopaedia of biochemistry. The programming has been performed in collaboration with a number of Diploma of Computing Studies students (M Kavanagh, A Kuffer, H Wreford). The initial version is nearing completion. In addition to the 'encyclopaedia' module, the system also includes 'test and teach' functions which allow users to access random questions, set questions, or tutorials on a range of topics covered on the videodisc. Using this software, students can access subject material through the videodisc encyclopaedia much in the way one might read a book, with the possibility of being guided through the material by tutorials, or simply being tested on their understanding of certain topics. The system has been tested with a videodisc containing material on basic developmental biology, however the software is generally applicable to videodiscs containing information on any subject. We are currently developing further the network of IBM-JX microcomputers for both tutorials and laboratory applications. The network has been operating successfully for the presentation of tutorials and simulations for one year. A similar network has been installed in the Department of Physics, University of Melbourne, where it is being used predominantly for laboratory-based classes. Software development is being performed largely in house, because of the limited availability of software covering subject material directly related to our courses. As more teaching programs become available for IBM personal computers, some of these programs may also be integrated into specific courses. More general use of authoring systems such as ,Q,1 may in future allow useful exchanges of completed lessons between departments and institutions. While much attention has in the past been focussed on the use of computers for tutorial style 'drill and practice', we are presently exploring other roles for computers in education. There are many possibilities for the use of computer-based simulations in biochemistry, as well as for the use of the computer as 'another tool in the laboratory' or in the management of experimental or administrative information.

References 1parslow, G (1984) Biochem Educ 12, 157-161 ZSawyer, W H (1972) Chem Educ 49,777-780 3McDougall, A, Sawyer, W H and Ciesieiski, V (1974) Technical Report 1, Computers in Education Research Group, University of Melbourne 4Learmonth, R P Livett, B G and Sawyer, W H (1985) Microcomputer based tutorial exercises for medical students in biochemistry, in 'Student control of learning: computers in tertiary education', Editors Bowden and Lichtenstein, University of Melbourne, pp 285-287 5Learmonth, R P (1987) Biochem Educ 15, 88-90