16

select a volume of enzyme, concentration of substrate, and pH; the computer then simulates a value for the rate of reaction by calculating an exact value from the Michaelis equation and adding a random error with a standard deviation of 3% of the value. In three hours more than 50 ‘results’ can be obtained; if carefully planned this allows the user to determine the enzyme’s optimum pH, its K, and V,,,,, at that pH, the effect of pH of K, and V,,, and the mode of action of a reversible inhibitor.

A New Approach to the Teaching of Experimental Design

John Garratt and Mary Aitken. Department of Chemistry, University of York, York YOI 5DD, UK

We have developed a series of classroom activities designed to allow students to develop the skills of planning and interpreting laboratory investigations. Each activity is based on a published paper which has been divided into short sections. A number of tasks are associated with each section, and students work on these in small groups. There is opportunity for interaction between students within their groups, between groups and with tutors.

Examples of the questions discussed are: (a) Why is the problem interesting? (b) What data are necessary and how should they be collected? (c) How might the data be presented and interpreted? At each stage, participants compare their proposals with those used in the paper, and discuss whether they could be improved on. This requires students to draw widely on their knowledge, and to apply it to a problem of greater complexity than could be tackled in a laboratory course. The study of this type of problem, to which there is frequently more than one correct answer, helps students to gain an insight into how scientists work.

Using ‘Miniposters’ to Reinforce the Teaching of Structure and Function of Biological Molecules

CHRISTOPHER A SMITH,* MAUREEN M DAWSON, MICHAEL B HEAD and MARTIN J JONES

Department of Biological Sciences the Manchester Metropolitan University Manchester MI 5GD, UK

Introduction Biochemistry forms a substantial component of the BSc (Hons) in Applied Biological Sciences at the Manchester Metropolitan University, although the specific Biochem- istry Units studied by students depends upon their point of entry into the course. Most students enter at the so-called ‘stage two’ and attend a three-year degree course, although a significant number enter at ‘stage one’ (the foundation year) and study for four years. This dual entry system allows recruitment of mature students and those with less conventional entry qualifications. This degree course is currently being reviewed and is likely to change in structure and entry requirements in the near future.

Biochemistry is taught both as a single honours subject or as a subsidiary subject on virtually all Life Sciences courses, although its learning and teaching often presents problems to students and staff respectively. The subject matter is sometimes abstract, and Biological Science

students often complain of difficulties in ‘visualizing’ biomolecules and metabolic processes. Students on general Life Sciences courses are usually strongest in the Biological rather than the Chemical or Physical Sciences, and this presents particular problems to the teacher. However, the structural data on biomolecules now avail- able from X-ray crystallography and nuclear magnetic resonance measurements and the use of advanced com- puter graphics means that models of molecules and simufations of their activities may be viewed and examined. These facilities undoubtedly aid student learning.

Preparation of posters The wide availability of molecular models was used with a stage one group of diverse ages and educational back- grounds (Table 1) attending a unit called Organic Chem- istry, Biochemistry and Cell Ultrastructure. As part of their unit assessment, students were required to prepare a ‘miniposter’ on the structure and activity of a specified protein, chosen for the students from a restricted list (Table 2). Proteins were used in this exercise because they are the most diverse of biological molecules in terms of structures and functions,‘.2 and thus numerous different examples are available for use with students. The poster preparation and presentation was used to reinforce the teaching by lecture and ‘wet’ practical classes of the hierarchical structures and the general functions of pro- teins. Hendrickson and Wiithrich3q4 are excellent sources of up-to-date references on the structures and activities of proteins and peptides.

The major restrictions imposed on the students were

Table I Educational background (‘A’ level studied) and age structure of the Stage 1 group which prepared the ‘miniposters’

GCE A level subject Number of A level passes

Art Biology Business Studies Chemistry Design Economics English General Studies Geography Government & Politics History Mathematics Medical History Music Philosophy Physics Psychology Social Biology Social & Environmental Biology Sociology

32

19

6 6

17 4

1 7

7 3

2

Mean age (years) 20 Age range (years) 18-36

*To whom all correspondence should be addressed

BIOCHEMICAL EDUCATION 22( 1) 1994