From Comprehension to Retention and Application in Molecular Biology for Medical Students

Harry R. Matthews

Department of Biological Chemistry
University of California at Davis

As multimedia makes concepts easier to understand, retention and application do not automatically follow as they did when students wrestled with opaque words and text. MoBy, a companion to multimedia presentations, helps students retain and apply the knowledge gained in lecture. MoBy uses a classical approach supplemented with hypertext, graphics, sound, and animations. It is available over the World Wide Web (WWW) at and on this CD. Problems have included cross-platform support and student tendencies to rely on MoBy alone. Nevertheless, MoBy has been highly successful, as judged by instructor perception and several hundred student evaluations.

"Molecular and Cell Biology" (BCM410A) is a required first year course for medical students that is taken by about 100 students each fall. There are no teaching assistants. The course comprises a lecture every weekday for 9 weeks--a total of 45 lectures. Most of the lectures are given by two co-instructors. The material focuses on the topic, protein structure and function in the human body. It is presented with extensive use of multimedia, using the power of graphics to illustrate the abstract concepts involved. The MoBy Study Aid is used in this part of the course.

Although students are highly intelligent and motivated, their backgrounds are enormously diverse--some are straight from a B.S. in Biochemistry or even a higher degree while others have no biochemistry background. Many have been out of school for several years. Students' computer skills vary from none at all to those of a professional software engineer.

Student performance is evaluated by two multiple-choice examinations, a mid-term, and a final. The quality of the course and the performance of each instructor are evaluated by written, anonymous, student evaluations and peer evaluation. Student evaluations are both quantitative and qualitative and are available for 4 years during the use of MoBy. Over 90% of the students in each year responded to our request for their evaluation. Evaluation questions and student responses for 1995 are found in Appendix 1. The questions change slightly from year to year but the questionnaire has not changed significantly in the last five years.

Course Software and Hardware

The technological tools center around Asymetrix's ToolBook program, with the addition of graphics from CorelDraw, ChemDraw and HyperChem, sound, and some animation. MoBy is being converted to run over the WWW (as opposed to just being downloaded), using a combination of HTML, Java, and JavaScript.

ToolBook provides excellent handling of hypertext, which is the basis of the application. More than 500 multiple-choice test questions form the core of the study aid. Most of these questions are of the "choose the best answer out of five choices" variety. For these questions, every answer choice has a page of explanation giving detailed information, test-taking tips, and whether the answer is right or wrong. These answer pages often include graphics. Probably the most useful feature is the glossary, which contains over 800 pages of detailed information, illustrated by graphics and some animations. Each glossary entry has one or more words that lead to it and every time one of these words appears in the application, there is a hyperlink to the glossary page. A question page will typically have 12 to 15 hypertext links per question; the same density is maintained throughout the study aid. Because there are over 3000 pages, this makes over 40,000 hypertext links. The answer and glossary pages often contain much more text than the questions. Thus, the dense network of links allows a student to "drill down" to a level that is accessible and then move up to the level needed to answer the questions. Intelligent navigation buttons keep the student from getting lost.

Access to questions is by subject or at random. Access to the glossary is direct, from an alphabetical index. MoBy is designed as a study aid, so it includes no form of assessment or tracking of a student's progress. Such facilities can be easily added in ToolBook but might inhibit students' use. Students should freely explore the glossary, find the animations and generally follow their interests, without worrying that someone might be metaphorically looking over their shoulder.

MoBy is available in the School of Medicine's student computer laboratory, which is always accessible to students and the Health Science Library student computer laboratory. There are more than 20 suitable computers available solely for student use, but with 200 students needing access, there is stiff competition during peak periods. Students with computers running Windows can take MoBy home--there are no royalty fees but unfortunately there is no Macintosh player for ToolBook applications. A new version of ToolBook will provide delivery as a set of HTML documents that might permit running MoBy over the Web, which may solve the problem of cross-platform support. An alternative approach, using Java and Javascript, is also being developed for the WWW.

Other Course Components

Twenty-three lectures use PowerPoint and a video projector linked directly to the computer (so that the animation features of PowerPoint can be used). The PowerPoint presentations are available to the students in the student laboratories and on the WWW ( /CoursePages/BCM410A/). Partial Macintosh support is available for these presentations. The cost of color printing and the lack of animation on paper prevents provision of printouts. Nevertheless, students do print out the slides.

Students communicate with the instructor through e-mail and I reply individually or, through a mailing list. Reading and responding to e-mail is an every weekday morning task. No attempt has been made to develop e-mail discussion groups, newsgroups, or chat sessions.

In addition, I hold traditional office hours daily and an informal review session weekly. There is an extensive printed syllabus, available on this CD.


A highly simplified classification of student learning is comprehension, retention and application. Comprehension requires that the student understand the material. Lecture or individual study of textbooks or other materials can achieve this. In many subjects, including the natural sciences, the use of graphical illustrations is important in helping the student understand the descriptions and concepts, which are sometimes abstract and counter-intuitive. In the lecture, graphics may consist of drawings on a black- or white-board, transparencies on an overhead projector, projected slides, video on a television screen, or computer images through a video projector. The black/white board has the advantage of showing each graphic in steps as it is built up. The computer can mimick this by using animated slides in which components are added one by one. The computer can also play animations, providing an extra dimension to the graphic. Careful use of graphics makes it much easier for students to understand the material. However, they may also mislead them into underestimating its complexity, which may cause difficulty in reproducing the material, explaining it to others, and using the material. Thus, the addition of sophisticated and successful graphics to a lecture class should be accompanied by material that helps students retain and use the material presented.

Concerning the remaining two learning characteristics--retention and application--the MoBy study aid uses the classical approach of asking questions. The questions that form the core of the study aid are those that have been previously used in internal examinations, which provides a powerful incentive to use MoBy.

No other incentive to use MoBy is provided or needed, as MoBy receives wide use. The critical component of MoBy is the extensive glossary and the explanations of wrong as well as right answers, often in considerable detail. Thus, MoBy is truly a learning aid rather than a testing tool. However, students need to understand that MoBy is a secondary learning tool for use when the material has already been covered and understood, at least at a superficial level. MoBy will help deepen the understanding and, by engaging the student with the material, help with retention and application.

Apart from the general question of reinforcing the lecture, MoBy helps address the problem of varying student backgrounds. The glossary allows students to go back as far as necessary to understand each problem.

Evaluation Data

A questionnaire to measure student appreciation included standard questions about the course as well as specific questions about the MoBy study aid. The questionnaire used in fall 1995 is provided in Appendix 1. The scale is 1 poor, 2 fair, 3 good, 4 very good, 5 excellent. Figure 1 shows how MoBy fared in the five years, 1991 to 1995.

Figure 1. Student evaluation of MoBy, 1991-95.
The students rated MoBy very good to excellent, with somewhat higher scores in 1992 and 1994 (also in 1996 when the score was 4.6/5). The reasons for the fluctuations are not known, but there are some factors to consider. The first year, 1991, was experimental. The year 1993 was unusual because of the presence of a significant group of students who did badly on the examinations. The drop in 1995 was at first surprising, but informal interviews with students suggested the reason may be that feedback from the 1994 class led the 1995 class to rely too much on MoBy, using it inappropriately to replace the normal lectures and associated studying. MoBy was not designed as a primary study aid, and so it failed to meet their expectations. Other problems are that MoBy only covers the material in 23 of the 45 lectures in the course and that there is no Macintosh version. In spite of these factors, MoBy still garnered a very good rating.

It is interesting to compare MoBy's rating with that for other components of the course. Figure 2 summarizes this comparison.

Figure 2. Student evaluations of various components of the course.

Figure 2 shows that MoBy ranked as one of the most valuable parts of the course, much higher than the textbook assignments and the co-op notes and comparable with the lectures. The syllabus was the most consistently valuable item. In some years (1992, 1994 and 1996) MoBy was at the top of the list, but over the other years there was significant variation in the score given to MoBy. The decline in textbook use is in line with trends elsewhere.


MoBy is greatly appreciated by students, especially those who can take the application home and work with it there. The instructor's perception is that it helps students greatly with retention and application but doesn't replace primary learning from the lectures and syllabus. Students regard MoBy as much more valuable than assigned readings in textbooks.

The format works well and requires very little computer expertise. The program, ToolBook, is most appropriate for this type of application because of its strong support for hypertext. Nevertheless, it was necessary to write some utilities to automate some of the authoring processes. ToolBook suffers greatly from lack of Macintosh support. This may be alleviated by the forthcoming Internet-friendly version. Most of the work in developing MoBy was in writing the questions, answers and glossary.

In informal conversations and in their written comments, many students have been extremely enthusiastic about MoBy as a study aid. It seems likely that this kind of approach would be of quite general application, especially in courses that use multiple choice questions in their examinations.

The version of MoBy that was used in Fall, 1996, can be installed from this CD and run on a computer using the Microsoft Windows operating system.

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