Objective examining — the Jena experience with preclinical students

164 some computers the areas of memory used for graphics fall in the middle of the space available for programs. Check as far as you can the mechanical reliability, particularly of the keyboard and power supply. If the computer is a new model, firm guarantees should be obtained from the dealer that any software promised will be available in the time stated and that service facilities will exist for at least three years. Prices quoted for identical computer systems vary widely, the author has received simultaneous quotations of £1300 and £1900 from different dealers, so seek quotations from a number of sources before purchase. Several quotations should also be obtained for software. Remember that, unless you are purchasing an integrated package of software and hardware, you are going to put a lot of effort into producing working programs. The best system for you will minimise that effort and will also be reasonably long-lived. The new generation of microcomputers now appearing will be more powerful, have prettier displays and have more personality than those currently available - - but are also more expensive. There is little that they could accomplish in a teaching situation that cannot be done on an already available machine. References Details may be obtained from CALCHEM, Department of Physical Chemistry, University of Leeds, Leeds LS2 9JT, UK 2 Biochemistry Microcomputer Group, c/o Department of Biochemistry, University of Liverpool, PO Box 147, L69 3BX, UK 3 Kibby, M R (1983) Biochem Educ 11, 143-147 4 Smith, S G, 'Introduction to Organic Chemistry', COMPress Software, van Nostrand Reinhold, UK

Objective Examining - - The Jena Experience with Preclinical Students H HOPPE, E HOFFMANN-BLUME, A HORN and H FRUNDER

Institute of Physiological Chemistry Friedrich- Schiller- University Jena, GDR Introduction Ten years ago we introduced an objective form of class tests and final examinations in biochemistry in our medical school. One of the reasons was the dissatisfaction with oral and written essay-type examinations. Another reason was to make the examinations free of real and imaginary imponderables between the examiners and the examinees. The method applied should (1) judge acquisition of information as well as comprehension and application, (2) automate the production of test sheets and the evaluation of answer sheets, and (3) test the quality of the questions posed and minimize the possibility of cheating. BIOCHEMICAL EDUCATION 12(4) 1984

Class tests and examinations performed according to the method developed have proved to be satisfactory means for testing the students' grasp of the subject matter under examination. Test Structure Our tests consist of statements grouped into parts I and II. In part I the 'open-book approach' is practised where students are permitted to consult textbooks and lecture notes when responding to 20 problem-based statements which requires a good understanding of the problems posed. In part II, 30 statements have to be responded to from memory alone. A total time limit of 120 min is set which is more than enough for an average student. At the beginning we applied multiple-choice questions. Later on, preference was given to the Glasgow True/False Scheme 1 because the questions can be formulated and handled easier than MCQs. Random guessing is discouraged by placing a premium on incorrect guesses I which makes a negative contribution to the score. The Appendix shows a test sheet as an example for a final examination (test sheets for class tests are available on request). Production of Test Sheets Questions are held in files on discs which can be readily accessed and from which one can produce test sheets with test items in any order desired. As a rule, four variants of test sheets are produced for one test which differ only by the order of test items (eg item 1 of the first variant is item 12 of the second one). This arrangement has proved to be satisfactory for minimizing cheating. The answer sheet has the same number for decoding the variant by the computer. Evaluation of Answer Sheets A sample of an answer sheet can be seen in Fig 1. Along the long sides of each sheet 50 double squares are numbered. The students have to cut out the outer square at the corresponding number when they are certain that the statement given in the test sheet under the same number is true. When they think it is false, both squares have to be cut out. If the students are not certain and do not want to answer, they make no cut at all. This "cutting procedure" shows practically no disturbances at the

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165 evaluation of the answer sheets whilst other marking procedures lead sometimes to difficulties when carried out by unexperienced students. The answer sheets are processed (~300/h) by an optical card reader and a desk calculator. The computer compares the student's response pattern as specified by a question setter, and tots up the score for each question in the following way. (1) For each alternative chosen which the setter considers correct + 1 is recorded. (2) For each alternative chosen which the setter considers to be incorrect - 1 . 2 is recorded. (3) For each alternative not chosen, no score is recorded. The accumulated positive and negative scores are reported together with the final score which is the difference between the two scores. In addition, a final grade is reported which ranges from 1 to 5, where 1 stands for an excellent passing grade, and 5 for failure. The mean score +1/2 SD (see legend to Fig 2) approximately denotes the range for a final grade of "3".

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Figure 2 Percentage distributions of the numbers of correct responses and final scores. The test described was administered to 154 examinees who reached a mean score of 20.4 + 8.1 (SO) The critical point on the grading scale is at the border line between passing and failure. Some time ago it was arbitrarily set at the point where about 15% of the examinees failed the test. Since then the border line has only changed minimally because we tried to elaborate different tests without great variations in test difficulty. This offers the possibility of comparing the results of different courses.

Evaluation of Test Accuracy In order to verify the accuracy of the test aimed at determining the extent of teaching efficiency and improving test items, an item performance analysis is carried out in terms of item difficulty, item abstention and item discriminatory power. Item difficulty (Li) and item abstention (Ui) are expressed as number of correct responses and abstentions to item i per total number of the examinees. Item discriminatory power which gives a numeric value for the capacity of item i to discriminate between the knowledgeable and less knowledgeable students, is calculated acBIOCHEMICAL EDUCATION 12(4) 1984

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Figure 3 Item difficulty and percentage of item abstentions. Item numbers on the abscissa refer to the test described cording to the point biserial correlation coefficient2 which we extended by taking into consideration also the item abstention (see legend to Fig 4). The extension was introduced since our students are always advised to choose item abstention rather than to use guessing in all cases when they are not certain. As can be seen from Fig 3, our students frequently use item abstention. The percentage distributions of correct responses and final scores of the test described in the Appendix are depicted in Fig 2. Due to incorrect responses, the final scores are lower than the numbers of correct responses. The extremes are a few examinees who depress their scores by excessive reluctance to mark any of the questions they are not absolutely certain about, and those who depress their scores still more by excessive guessing. All this information is helpful for improving the educational process. The item difficulty and the percentage of item abstentions are depicted in Fig 3. Only a few items seem to be too easy. There are, however, some items with a very low percentage of correct responses and a high number of abstentions. A thorough analysis revealed that the corresponding topics were either not dealt with properly in lectures and seminars (items 5 and 48) or the questions were not posed as unambiguous as possible (items 29 and 34). The item discriminatory power plotted against the item difficulty is shown in Fig 4. About half of the items show a reasonably good discriminatory power which is largely independent of the item difficulty. A very few items show no discriminatory effectiveness and are, thus, deficient for a number of reasons. They have to be discarded. The remaining test items show only a modest discriminatory power. Class discussions are often very useful for improvements in the formulation of such questions.

Discussion Our results agree with previous reports 3-7 on the advantages of objective examinations which greatly contribute to counselling, evaluation of teaching, improving learning and formal student student assessment. The results of our

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tive tests and provides more benefit for the educational process than lengthy oral examinations at the end of a course when "the train has left". Many students ask for test sheets from previous courses and use them frequently for self-assessment. Short tests with 4-6 simple test items are regularly applied at the beginning of the weekly seminars in order to assess the minimum preparation for the seminar. The whole procedure lasts about 5 minutes. Two students of the group mark the small test slips produced by a punch-tape directed automatic typewriter by hand during the seminar and report the results. Students not properly prepared resit after a few days. Four different types of test slips are sufficient for minimizing cheating in a group sitting closely together. After the test the seminar proceeds in an open and relaxed atmosphere without any further assessments which greatly contributes to an unrestrained and lively discussion.

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References where XR(~ = mean score of all examinees who correctly responded to item i, D~(i~ = mean score of all examinees who incorrectly responded to item i, f(u(i) = mean score of all examinees who abstained from responding to item i, a~ = standard deviation of the scores, Li = item difficulty and Ui = item abstention (see text). The quotient (Xz~(~)-f(R(i;)/ffx is omitted for items without incorrect responses in order to avoid unjustified high Ti values.

Buckley-Sharp M D and Harris F T C (1971) Brit J Med Educ 5, 279-288 Hubbard J P and Clemens W V in Multiple-Choice Examinations in Medicine pp 63-64 (1961) Lea & Febinger, Philadelphia Cox R (1972) Nature 237,489-492 Headon D R and Ross C A (1976) Biochem Educ 4, 28-29 Bryce C F A (1979) Biochem Educ 7, 67-69 Morgan M R J (1979) Biochem Educ 7, 84-85 7 Iborra J L and Lozano J A (1980) Biochem Educ 8, 57-59

Appendix Computer-produced test-sheet as an example (final examination). This is reproduced directly here as a mini-print: it will be clearly readable with a magnifying glass. Part 1

final examinations correlate excellently with the achievements of the students in practicals and seminars (r=0.70) and also with the results of lengthy oral examinations in physiology and anatomy (r--0.55). With a very few exceptions, good students collecting a high percentage of the possible scores in part II of the test collect nearly all possible scores in part I. Weak students not collecting too many scores in part II are still worse in the open book approach of part I. The True/False type of items applied, although generally less common, measure not only the acquisition of information but also comprehension and application. The problem with guessing seems to be reasonably restricted by the scoring procedure applied. The subjective element which lies in the setting of questions and applying scoring criteria has been reduced during the years by discussions with the staff and the students and by evaluation of the test items. The ease of administration of these tests with automated production of test sheets and evaluation of answer sheets frees the staff from cumbersome occupations. Staff time saved by this automated procedure is spent throughout the course for extending staff-student contacts with the main emphasis on discussion and clarification of ideas. This also compensates for some disadvantages of objecBIOCHEMICAL EDUCATION 12(4) 1984

A) A o a t i e n l w i l h a s e p t i c i n f e c ~ i o n , a t ~ p e ~ a t u ~ e o f q O 3 ~ l ~ g ~ e e ~ r C ~ v e r y low blood p r e s s u r e and Massive b l e e d i n g ~ro~ t h e n o s e ~ i n l e s t i n e and u r i n a r y t r a c t i s a d m i t t e d t o the i n t e r n a l c l i n i c He i m M e d i a t e i p r e c e i v e s a t r a n s f u s i o n o¢ 500 M1 h e p a r i n i z e d f r e s h blood a n d , i n a d d i t i o n ~ t h e r a p y w i t h a n t i b i o t i c s i s s t a r t e d . B e f o r e and s h o r t l y a£xer the t r a n s f u s i o n thd ~ o l l o w i n g data are recorded i n h i s blood and b l o o d plas~a~ beTore o t t e r normal range transfusion ~hro~bocytes (Eg/1) 10 20 106-300 ¢ibrinogen(Mg/1) 500 600 3000-5000 plasMinogen ( M q / I ) 2 15 I00-200 antithroMbin III (Mq/l) 5 I0 I00-200 The h a l ¢ - l i ~ e t i ~ e o~ i n t r a v e n o u s l y a d ~ i n i s t e P d a n t i t h r o ~ b i n I I I i n b l o o d plasma i s 7 h ¢nor~al range = 50-100 h ) . ~

Sequencing o~ a DNA segment b~ the c h a i n ~ e r ~ i n a ~ i o n ~ethodlUnder c o n t r o l a s i n g l e s l r a n d e d DN~ t e m p l a t e w i t h an unknown sequence~DNA polyMerase s y n ~ h e t i z e d , b e g i n n i n g a~ ~he 3 ' e n d o¢ • p r i m e r DNA frag~enx~DNA o l i g o n u c l e o t i d e s o¢ l h e ¢ o l l o w i n g c h a i n l e n g l h i n ¢our s e p a r a t e i n c u b a t i o n s , n a m e l y i n the i n c u b a l i o n w i t h ~ ' ~ 3 ' - D i d e s o x y - T T P c h a i n s w i t h 4~7 and 8 bases~ 3 ' - S i d e s o x y - A T P c h a i n s w i l h 3 and 10 bases~ ~3'-Didesoxy-CTP c h a i n s ~ i t h I ~ and 5 bases~and i n the i n c u b a t i o n w i t h 2 ' ~ 3 ' - D i d e s o x y - G T P c h a i n s ~i~h 6 and 9 bases.

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C) 10 ~in a ~ e r the b e g i n n i n g o~ an o p e r a , i o n c a r r i e d ou~ under h a l o l h a n e anes+hesia~lhe p a l i e n l appeared p a l e and c y a n o l i c H i s blood p r e s s u r e had f a l l e n ~o 80 ~N Hq)and h i s p u l s e r o l e had r i s e n ~o 170 pep ~ i n . H i s s k i n aas ho~ and sweaty and ~ u s c u l a r s l i f f n e s s occured i n d i f f e r e n ~ s e t s o¢ v o l u n t a r y muscles.No a c t i o n p o t e n t i a l s c o u l d be seen i n the ~yogra~ o f ~he s t i f f ~usclee a f t e r ner~ s ~ i ~ u l a t i o n . A n e s l h e s i a and o p e r a , i o n ~e~e f i n i s h e d w i l h i n ~he ne~t 5 ~ i n . T h e p a t i e n t r e ~ a i n e d unconscious ~or an a d d i l i o n a l b~ ~ i n w i t h • sweaty s k i n and a r e c t a l ~e~perature o¢ 41 degrees ¢ . B l o o d i n v e s t i g a t i o n s p e r ¢ o r ~ e d d u r i n g I b i s p e r i o d r e v e a l e d a combined ~ e ~ a b o l i c and r e s p i ~ a l o r y a c i d o s i s . T h e p a t i e n t g r a d u a l l y r e c o v e r e d u i ~ h i n t h e n e x l h a f t e r w h i c h no a b n o r m a l i t i e s ~e~e d e t e c t e d . Re~arke on t h i s syndrome which i s c a l l e d NALZGN&NT HYPERTHERMIA and which was no~ ~rea~ed i n l e c l u r e e and seminars. When a suspension ~¢ non~al i s o l a t e d ~ I t o c h o n d r i a i s exposed to 3 m H h a l o t h a n e ~here i s • I o l s o~ r e s p i r a t o r y c o n t r o l and • d r a s ; i c f a l l o¢ ~he P/O r a t i o . F r e e f a l t y a c i d s q P e ~ l y I n c r e a s e . Thes~ e f f e c t s o¢ h a l o t h a n e are a b o l i s h e d by a d d i t i o n ~f C a - c h e l a t i n g agents ~o ~he ~ediu~. I n d i v i d u a l s d e v e l o p i n g ~he ~alignan~ h y p e r l h e r ~ i • s y n d r o a e d u r i n g a n e s t h e s i a p o s s e s s a ~ e n e t i c p r e d i s p o s i t i o n u h i c h c r e a t e s an i n t o l e r a n c e towards h a l o • h o n e and o~her halagenated a~es~he~ics. One h y p o t h e s i s conqruen~ w i l h ~he o b s e r v a t i o n s d e s c r i b e d above assu~es t h a t ~hese i n d i v i d u a l s possess Ca-dependent p h o s p h o l i p a s e s ~ i x h increased C a - a f f i n i t y . These m u t a n t enzymes a r e ~aPkedly ~ore a c t i v a t e d than t h e induced by about 1

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I A The l a b o r a t o r y f i n d i n g s recorded b e f o r e the ~rans~usion lead to the c o n c l u s i o n ~ t h a t t h e r ~ i s e i t h e r an i n h i b i t e d s y n t h e s i s or an i n c r e a s e d consumption o~ x h r o ~ b o c y x e s ~ c l o t ~ i n g p r o t e i n s and c l o t t i n g i n h i b i t o r p r o t e i n s . ~. A l l data t o g e t h e r are i n d i c a t o r ~ ~or the dEagnusis ' b l o o d c l o t t i n g d i s t u r b a n c e ~ecause o£ an increased consumption o~ c l o t t i n g f a c t o r s w i t h a cocoNxtant hyper£xbrlnolysi~ 3A. I t can be expected t h a t the c o n c e n t r a t i o n o£ alpha ~ ~ a c r o g l o b u l i n i n the p a t i e n t ' s b l o o d plasma i s n o r m a l 4A. Heparin does not i n h i b i t b l o o d c l o t t i n g i n ~he absence o~ a n ~ i t h r o ~ b i n I l l . 5A. l n h i b i t o r s o£ c y s ~ e i n e p r o t e i n e a s e s ¢ t h i o l p r o t e i n a s e s ) i n h i b i t blood c l o t t i n g . hA. Strong s t i m u l a t i o n o¢ phagocy~os~s induces a r a p i d decrease o~ the plasminoqen c o n c e n t r a t i o n i n blood plasma.

167 7A. I T can be deduced Pro~ the p a t i e n t ' s data t h a t h i s t h r o ~ b o p l a s t i n Ti~e w i l l be s h o r t e r t h a n n o r m a l 8 B . A c c o r d i n g t o the data g i u e n , ~ h e unknown DNA ~e~plaTe segment has t h e sequence 3 ' -G~G-T-A-G-C-A-A-C-T-5 ', ~ T~e ~eq~e~Ee o~ T h ~ u n k n ~ . ~ DNA ~ e ~ e una~biguousl~ Cro~ the data given.

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IOB. DNA-dependent RNA p o l v ~ e r a s e s t r a n s c r i b e DNA only i n the presence oT DNA Crag~ents a ~ p r i ~ e r s , l I B . The c h a i n T e r m i n a t i o n ~ethod can be a p p l i e d fa RNA sequencing a¢~er copying the RNA ~e~sage by u s i n g r e u e r s e ~ r a n ~ c r i p ~ a s e . 12B, DNA p o l y ~ e r a s e s ' r e a d " t e m p l a t e DNA s t r a n d s i n 5 " - 3 ' - d i r e c t i o n and s y n t h e t i z e complementary c o p i e s i n 3 ' - 5 ' - d ~ e c t i e n . 13B. DNA-dependent DNA p o l y ~ e r a s e s need s i n g l e s t r a n d e d DNA t e m p l a t e s and RNA p r i ~ e r s Cur DNA r e p l i c a t i o n i n ~he E-phase ~ the c e l l c y c l e , 14C. The a n e s t h e s i a induced p r o t o n l e a k s i n the i n n e r ~e~brane uP the patient's ~itochondria. 15C. A d m i n i s t r a t i o n o¢ the c o u p l i n g i n h i b i t o r o l i g o ~ y c i n =ould e x e r t a Cauourable t h e r a p e u t i c e¢¢ect o n t h i s syndrome, 160, The r a p i d i n c r e a s e o~ the p a t i e n t , s t e m p e r a t u r e i s the consequence o~ an i n c r e a s e d ATP h y d r o l y s i s . 170, The ~ u s c l e s t i ~ n e s s observed i s due t o ~ e t a n i c ~ u s c l e c o n t r a c t i o n s . IBC, Th r a t e o? ATP g e n e r a t i o n i s lowered i n the p a t i e n t ' s heaP~ ~ u s c l e . 190, The ~ e ~ a b o l i c a c i d o s i s observed i s The consequence o£ an increased ketone body C o r r o s i o n i n s t r i a t e d ~ u s ¢ l e s . 290. Pi c o n c e n t r a t i o n i s d r a s t i c a l l y increased i n t h e p a t i e n t ' s ~o~cles d u r i n g t h e a c u t e phase o~ the d i s e a s e ,

Part 2 ? I . A M i x t u r e o¢ the p r o t e i n s A,B and C w i t h i s o e l e c t r i c p o i n t s o f 2 , 4 and 6 i s Miwed a~ pH 3 wi~h a c a t i o n e x c h a n g e r . O n l y p r o t e i n A w i l l he bound t o the exchanger under ~ h e s e c o n d i t i o n s , 22. P r o t o n s are bound t o hemoglobin d u r i n g t r a n s i t i o n o f deoxygenated hemoglobin t o oxygenated hemoglobin, ; ! 3 , Doubling o f the e n z y m e c o n c e n t r a t i o n h a l v e s t h e K~ oF t h e e n z y m e Cur i t s substrata. 24. The co~pound 'OOC-CHS-COSCoA i s the r e a c t i o n p r o d u c t o~ t h e enzyme acetyl-CoA carbox~lase. 25, Lipoxygenases transqoeM a r a c h i d o n i c a c i d i n t o c y c l i c e n d o p e r o x i d e s , 26, Occupation o¢ beta~adrenergic r e c e p t o r s o~ s~ooth Muscle c e l l s with a d r e n a l i n ehcits d e p o l a r i s a ~ i o n and c o n t r a c t i o n v i a cAMP-dependent r e a c t i o n s , 27. Occupation o¢ i n s u l i n r e c e p t o r s o~ ~ t r i a t e d Muscles wi~h i n s u l i n e l i c i t s a r a p i d i n c r e a s e o~ the nu~beP o¢ g l u c o s e t r a n s p o r t e r s i n the sarcoleMMa, 28, P h o s p h a t i d i c a c i d c o n s i s t s o¢ s p h i n g o s i n ~ ¢ a ~ t y acid and p h o s p h o r i c a c i d . 29. The c y t o l y t i c complement complex d e ~ t r o y s c e l l ~eMbranes v i a i t s p r o T e i n a s e and p h o s p h o l i p a s e a c t i v i t i e s . 30. I n h i b i t i o n o£ the enzyme p o r p h o b i l i n o g e n synthase e l i c i t s an i n c r e a s e d e x c r e t i o n o£ d e l t a - a ~ i n o l e ~ u l i n i c acid i n the u r i n e . 31. The t r a n s ? o r ~ a t i o n o8 b i l i r u b i n i n t o u r o b i l i n o g e n takes p l a c e i n h e p a t o c y t e s , 32, A r e s p i r a t o r y a l k a l o s i s induces a decrease o ¢ t h e 2~3-bxsphosphoglycera~e c o n c e n t r a t i o n in erythrocy~es. 33. A d m i n i s t r a t i o n o¢ i n h i b i ~ o r s o¢ c a r b o a n h y d r a t a s e induces a decreased e ~ c r e t i o n o¢ p r o t o n s and a decreased r e a b s o r p t i ~ n o¢ HC03' i n the k i d n e y . 34, E h i c i e r o r a l a d m i n i s t r a t i o n o? r a d i © a c t i u e i o d i d e ~he t o ~ a l r a d i o a c t i v i t y i n ~he p a t i e n t ' s b l o o d ~las~a i s h i g h e r than normal and a¢~er 4~ h l o w e r , T h i s i s t y p i c a l o~ the d i a g n o s i s " h y p e r ~ h y r e ~ s i s ' , 3 5 ~everse t r a n s c r t p t a s e belongs ~o the RNA-dependen~ RNA p o l y ~ e r a ~ e s . 36, An i n c r e a s e d l i p i d p e r o x i d a t l o n induces an increased ¢lu~ o¢ g l u c ~ s e - 6 - P through the o x i d a t i v e p a r t o~ the pentose phosphate pathway . 3 7 . 1 n h i b ] t o r s uP d ] h y d r o ~ o l a t e r e d u c t a s e i n h i b i t de hOVe s ~ n t h e s i s o¢ p u r i n a r i n g s 3~ 'OGC-CHN+H3-CH2-CH~-CHSN+H3 f u n c t i o n s as s u b s t r a t a xn ~he urea c y c l e , . 3 9 A sample ~ a woman's u r i n e i s ~ i x e d w i t h a n t i b o d i e s a g a i n s t hCG.ACter a d d i t i o n o~ e r ~ t h r o c y t e ~ loaded w i t h hCg ~o t h i s M i x t u r e the e r y t h r o c y t e s clump and r a p i d l y sediment,The r e s u l t oT t h i s e a r l y pregnanc~ t e ~ i n d i c a t e ~ t h e e x i s t e n c e o ~ a pregnancy. 4O. The energy e ~ p e n d i t u r e d u r i n g p h y s i c a l work u i t h a consumption ~¢ 3 , 5 i 0 2 / ~ i n wa~ ~e~ by combustion o¢ each 5g~ c a r b o h y d r a t e s and ~ a t t y a c i d s , U n d e r t h e s e c o n d i t i o n s ] q ? a r t y a c i d s and 2 g g l u c o s e or glycogen g l u c o s e are o x i d i z e d t o 002 and HSO per ~=n. The c a l o r i f i c or C u r l v a l u e o~ t 1 02 consumed i s 20 kJ. 41.The p r o t o n c o n c e n t r a t i o n o~ a s o l u t i o n c o n t a i n i n g I ~M NaHSP04 and 10 ~M Na;~HP04 a~ounts t o I , S B * E - 8 M (pK* o¢ the second d i s s , s t e p o¢ H3P04 : 8 8 ) , 4 2 . I n the l i n e a r p a r t ~ the c a l i b r a t i o n curue~2 ~g p r o t e i n y i e l d an O,B,oF 0.25~ Under ~den~i~al ~est c o n d i t i o n s P.02 ~ l b l o o d ~eru~ y i e l d an O.D.o? B,30,Then, the o r o t e i n c o n c e n t r a t i o n aeount~ t o 9 g per 100 ~ l blood serum. 43,A v i t a m i n ~ 1 2 d e £ i c i e n c y l e a d s t o d i s t u r b a n c e s o¢ the t r a n s ? o r ~ a t i o n o? ho~ocystein i n t o ~ e t h i o n i n . 44.Th~ ' s a l v a g e s y n t h e s i s ' o ¢ p u r i n a n u c l e o t i d e ~ needs t r e e p u r i n a ba~es and phosp~or~bosy]pyrophosphate as s u b s t r a t e s , 45.The t e r ~ 'pro~n~or DNA' denote~ a DNA segment a t the 5 " - e n d o~ ~ t r u c t u r a l 9ene~ which s nol t r a n s c r i b e d . 4 6 S c r e t ~ n induces t h e s e c r e t i o n o£ a H O D 3 ' - r i c h p a n c r e a t i c j u i c e . 4?.The adenine o l i g o n u c l e o t l d e 2 " - 5 ' - A , w h o s e s y n t h e s i s i~ induced by i n t e r f e r o n a c t i v a t e s a RNA endon~clease p r e s e n t i n MOSt o f our body c e l l s . 4 8 1 h ~ Rappa pen segment,which i s r e s p o n s i b l e f o r coding the UL-don,}in o f t h e kappa l ~ u n o g ~ n b u ] ] n l i g h t c h a i n ~ s ?or~ed by c o m b i n a t i o n o? each a Ukappa and a ,Ikappa pen segment d u r i n g d i ? ~ e r e n l i a t ~ o n o ? B-19~phocyles i n the bone marrow. 4 ~ A n a g o n t s r ~ o? u i t a ~ i n K i n h i b i t The p o s t ~ r a n s l a t i o n a l d e c a r ~ o ~ y l a t i o n o~ pr~teln-hnund Clluta~c actd ~ l O . K e ~ e n z y m e , , o~ c a t a b o l i c

residues pathways

o~ d i f f e r e n t clo~ting proteins. are ina(:tJuared by protein pho~phorylatlon

Conference on Chemical Education: Impressions by a Chemistry-teaching Biochemist A REPORT BY V VERSI~E* While Biochemical Education published Strategies of Biochemical Education (A H Mehler, in the July 1983 issue), chemists were preparing the 7th International Conference on Chemical Education (ICCE) Like many other biochemists, I also teach practical classes in general chemistry. Therefore I decided to attend the above meeting and on 21st August I entered the Hall of the Universit~ des Sciences et Techniques du Languedoc at Montpellier, France, in search of solutions to specific * Faculteit Geneeskunde en Farmacie, Vrije Universiteit Brussel, Brussels, Belgium. BIOCHEMICAL EDUCATION 12(4) 1984

teaching problems. Ninety-nine percent of these problems have to do with the specific objectives of our education programme and the particular circumstances in which we are working. As it happens, I went home without the answers, but with the feeling that any biochemist, involved in education, would have gathered interesting information. Conference Organization The ICCE is organized bi-annually. The last one was held in Maryland and the next one is planned in 1985 in Tokyo. This year's conference was sponsored by IUPAC and CNC. (Comit~ National de la Chimie) in collaboration with UNESCO on the general theme 'Chemistry, Education and Society'. Seven hundred participants from about 60 countries developed this theme during one week through various activities: plenary sessions, seminars, workshops and posters. I will comment shortly on each of these. Plenary Sessions Different speakers evoked the growing agreement among chemists about the need for better chemical education for everyone. Little research on the place taken by chemistry in the development of a human being has been done and, as R Viovy made clear, this research should be undertaken. There was no need for research to realize when listening to J Benard's lecture that chemists from all over the world shared his impression that the image of chemistry is poor. While chemistry permeates most human activities to a greater or lesser extent, the attitude of the man in the street towards chemistry is all too frequently negative. Important concepts are often poorly understood, examples being the relation of concentration to toxicity and the identity of natural and synthetic substances. The results of F Tambute's small-scale enquiry among her pupils clearly illustrates the feeling of many chemistry teachers: chemistry is a subject that is disliked. To the question: "Does it appear to you as though chemistry forms part of your daily life?", 80% answered N O and 20% could only think in terms of a relationship between the discipline and pharmaceuticals or synthetic fibres. R Kempa put forward the idea that we should shift our priorities in chemical education from an early emphasis on the education and training of future chemists to the present endeavours at portraying chemistry as a socially relevant and responsible pursuit. This means a shift from education in chemistry to education about chemistry, Furthermore, chemistry has developed rapidly over the past few decades while many of us have remained attached to older teaching methods and matters. F Tambute and J Holman informed the audience of new pedagogical approaches for the second stage of education in France and the United Kingdom respectively, which stress the social relevance of the chemistry taught. Valuable teaching material, and a survey of the work done in England, are available from the Association for Science Education (College Lane, Harfield, Hertfordshire, UK). J Benard strongly recommended the re-establishment