Advanced Topics in Gas Chromatography Series: Deri~ati~es Chromatographic Screening of Drugs the NMR Phenomenon
DNA: Blueprint of Life
The Chemical Shin Basic Liquid Chromatography The Column
Communication Skills Corporation, 1220 P a t Road, Fairfield, Connecticut 06430.35mm slide audio tape packages. The use of teaching modules consisting of color slides in cambination with prerecorded tapes is becoming increasingly common. Low cost and the ease with which slideltape programs can he edited makes them appear less formidable for the amateur t o produce than films or film loops. A large number of commerciallyproduced slideltape programs are also currently available. A discussion of the merits of slide/tape modules, therefore, seems .timely. What role can slideltape modules play in the teaching of chemistry? To this reviewer their strength lies in teaching manual skills and procedures. For example, consider teaching the use of a pipet. A few slides and some brief taped comments can impart information about correct procedures much more accurately and easily than a page of carefully written instructions. In this situation a slide/tape module a t its best can approach one-to-one personal instruction. Slideltape modules are not effective replacements for textbooks or for classroom lectures on fundamentals. A taped lecture illustrated by slides containing equations. diagrams, and tables is just as bad as the paper you walked out on during the last ACS meeting-the one that was read word-for-word and illustrated by a profusion of slides that were on and off the screen before you could make any sense out of them. Perhaps a n effective distinetion between the proper and improper use of slideltape modules lies in the questions that the student may be expected to ask about the material. If most of the student's questions can he answered by quick reference to the slides (Where should 1place my finger? Which knqb should I turn?), the use of slide/tape modules should be considered. If the questions are more abstract (What is a Lewis acid? Whv are those two structures different?)., stick to a bwk or a lwe lecture. The rtrrngths and weaknerres of s l ~ d r / t a p e inrtructhn are illustrated in tnese programs r e r ~ n t l yproduced by Communication Skills Corporation. "chromatographic Screening of Drugs" is an effective lesson in the qualitative analysis of drugs by tle. (Despite its appearance in a series on gc, the program contains very little information about eas chromatomaohv.) The analvtieal orocedures are shown step-hg->repin \er) clear photographs that comprise most of the procram and the fapen narration rrmplments the slides. This program would do very nicely as a training aid for technicians; it might also find use in colleges as an illustration of the application of simple analytical techniques to the solution of an important and complex problem. The other modules are examples of the misapplication of the slideltape technique. They consist almost entirely of tables, graphs, or text. The narration is often little more than a reading of the slide with minimal embellishment. To be sure, the slides are more colorful than typical book illustrations, but the overall teaching effectiveness of these programs is certainly inferior to a good monograph, and you can purchase four expensive monographsfor the price of one program. The level of the CSC programs is very uneven. The advanced gc program on derivatives begins with an elementary discussion of vapor pressure and hydrogen bonding. The basic liquid ehromatography program assumes a n understanding of the terms polarity and ionic strength. Those concerned with details will be unhappy with some aspects of the programs. For example, structures are sloppily and inconsistently drawn, there is a lack of precision in some definitions, the words adsorbent and symmetrical are misspelled, and the narrator mispronounces some terms. For the most part the slides are clear, but the variation in type size within one slide and the layout are sometimes illogical. Portions of some slides are likely to he illegible when viewed on a small rear projection screen. The correction of these flaws calls for the strong hand of an editor. The Teachers Guide supplied with each program consists of a list of the slides, a hibliokaphy, and some suggested discussion topics. Programs are available on a thirty-day trial. Those considering utilizing them should certainly make use of this offer. ~
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C. N. Knobler University of California at Los Angeler
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Journal of Chemical Education
17 min. 16mm color/sound film. $200.00 This film makes use of animation, time-lapse photomicroscopy. and electron microscopy t o describe the structure and function of DNA. It shows the pmcess by which the information in DNA is used as a blueprint for the synthesis of proteins. It also depicts proteins, chromosome division, DNA structure and replication, the use of RNA t o transfer the DNA message, and the synthesis of proteins with the aid of RNA and the ribosomes.
Origin of Life: Biochemical Evolution 25 mi". 16mm color film. $300.00 The first part of this film answers the question "what is life?" in biochemical terms. It introduces basic concepts in chemistry like the chemical bond and then describes the structure and funetion of lipids, carbohydrates, proteins and nucleie acids. The second part "How Life Began" traces the evolution of life on primitive earth from carbon, oxygen, nitrogen, and hydrogen. It shows how amino acids and other organic compounds can be spontaneously synthesized from simple gases. Then it covers polymerization of the simple organic compounds, formation of cells from palymers, the evolution of photosynthesis resulting in the release of oxygen into the atmosphere, and the evolution of life forms that use oxygen.
Proteins: Structure and Function 15 min. 16mm color/sound film. $185.00 Uses 3-dimensional models and animation t o show the chemical structure of protein and several 3-dimensional configurations of proteins, including trypsin. It depicts the type of interactions that determine 3-dimensional structure in the protein, such as hydrogen-bonding and hydrophohie-hydrophilie interaction. The film shows how proteins function as a major component of the structure of living organisms and as catalysts to control the chemical reactions of life. It illustrates the active sites of trypsin and chymotrypsin as examples of how enzymes work. All available from John Wiley & Sons. h e . , 695 Third Avenue, New York 10016. All three of these films are well done, the animation sequences being particularly effective. Some scenes are oversimplified a bit, such as the depiction of amino acids in molecular rather than dipolarionic form, but the films on the whole are accurate. The level of presentation is best suited for students in introductory courses, although teachers of more advanced courses could well use many of the animation segments as lecture aids. It is a bit disconcerting t o note the somewhat dogmatic treatment of origin of life and evolution. Teachers using the films would he well-advised to discuss with their students the true limitations of scientific theories and mechanisms. Rod O'Connor Texas A & M University College Station, Texas 77843
New Aids Video Player Kodak announced that they intend to manufacture and market their Super 8 Video Player (W-11, priced a t $1195, with immediate deliveries. On the video player, conventional Super 8 films can be shown in a color television home receiver, or the film can also be projected, if desired, on a conventional Super 8 projector. The implications of future use and application of the Super 8 video player are impressive. One use often overlooked might be the application of this unit to closed circuit operations. The Kodak Supermatic film videoplayer W-1plays black-andwhite or color, silent or sound super 8 motion picture over a standard color television set by attachment to the antenna terminals of the set. The videoplayer can also feed a signal to a multiplicity of television sets or a television system. Features of the Kodak Supermatic film videoplayer include pushbutton controls, automatic threading, instant review, stop motion, cassette loading, automatic rewind of film into the cassette a t the end of the film, and extremely quiet operation,
