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Fertilization and its Biochemical Consequences
BIOCHEMICAL EDUCATION i
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Fertilization and its Biochemical Consequences By Alberto Monroy. Pp. 38. Addison-WesleyPublishing Company. 1973 $1.00 (Paperback).
January 1974 Vol. 2 No. 1 i
19
H|
It also has something for the more curious graduate student not specializing in problems connected with fertilization of the animal egg. J.R. Tata
The series of small monographs published as Addison-Wesley Modules in Biology represents a welcome attempt to filla significant gap in scientificcommunication. H o w successful such a venture'is likely to be for biochemical education depends on the selection of topics and authors. The subject of differentiation is attracting increasing attention from molecular biologists and Professor Alberto Monroy is an authority on the biochemical basis of differentiation. It is therefore easy to predict that the 7th "module" on "Fertilization and its Biochemical Consequences" by Professor Monroy is bound to be a success.
In 37 pages Professor Monroy has covered a wide range of phenomena concerning the maturation and the early events following fertilization of the animal egg. The "module" is divided into two parts. The first part describes the morphological and physiological changes taking place after fertilization and the second covers the biochemical changes. The introduction gives a simple definition of "Fertilization" and a very brief but succint summary of the most important events immediately after fertilization. Two major aspects of morphological and physiological changes covered are a) garnets fusion and formation of the zygote nucleus, and b) the structural changes noticeable in the fertilized egg, with particular attention paid to changes in cortical granules, the viteUine membrane and the hyaline layer. The morphological description is adequately supported by illustrations (4 line drawings and 8 photographs). There is an impressive reproduction of a scanning electron microscopic view of the sperm-egg interaction but unfortunately the quality of most photographic reproductions is poor - perhaps due to the necessity of keeping down production costs. In describing the biochemical aspects of fertilization, Professor Monroy very judiciously begins with an account of the process of oogenesis, particularly the elaboration a , d storage of information in the form of DNA, RNA and proteins of the mature egg. The rest of the biochemical coverage largely concerns the activation of stored maternal messenger RNA and the transcription of embryonic nuclear DNA after fertilization. The conclusion drawn is that both these processes occur simultaneously. All the other biochemical changes are extremely briefly covered under "fertilization-dependent metabolic changes" and one wonders whether it would not have been preferable to leave this last bit out altogether. A major criticism of this otherwise fascinating account of fertilization is that it is too narrowly based on Professor Monroy's own interest in the control of protein synttfesis during fertilization of the sea"urchin (and frog) egg. It could be argued that it is wrong to generalize from eichinoderm and frog eggs, which are fertilized and develop independently of maternal influences, to mammalian eggs which are under maternal (and placental) regulation for a considerable time after fertilization. It is also known that, unlike frog and sea urchin eggs which lay down a large enough store of maternal ribosomes to support protein synthesis beyond gastrulation, development of fertilized mammalian eggs is dependent on ribosomal RNA synthesis from the four-cell stage onwards. The disproportionate emphasis on regulation of protein synthesis - albeit most important for differentiation - may give a misleading impression of a minor role played by processes such as control of permeability, membrane function and metabolite gradients during differentiation. These shortcomings should not detract from the lucid style and the authoritative account of regulation of protein synthesis before and after fertilization of the egg. Professor Monroy's "module" should be a valuable adjunct to the standard undergraduate courses in biochemistry and developmental biology.
National Institute for Medical Research, Mill Hill, London, U.K.
Biochemical Reasoning. Numerical Examples for Students Edited by D. Kerridge& K.F. Tipton, W.A. BenjaminInc. Hardback£8.15; Paperback£2.60. The last few years have witnessed the publication of several new books presenting numerical and problem-solving aspects of biochemistry and the initial reaction to Biochemical Reasoning might well be "What, another?" However, the present collection differs from its predecessors by placing greater emphasis on the interpretation of experimental data, providing extensive hints on the solution of the problems and comprehensive answers, while eschewing any formal supporting text on the topics covered. The questions have been constructed, principally from the original literature, by members of the staff of the Biochemistry Department at Cambridge. The book is divided into three sections, the first presenting 57 questions (78 pages), the second (34 pages) giving hints for their solution, and the third (125 pages) proving the detailed answers. An appendix and index complete the work. The questions "fall into five sections, namely, The Structure of Macromolecules (13), Enzymes (20), Respiration and Photosynthesis (5), Microbial Growth and Metabolism (8) and Molecular Genetics and Biosynthesis (11). Within the framework a wide range of experimental topics is covered and a student who, during his course, has worked his way conscientiously through most of them will certainly have a good grasp of the scientific reasoning underlying current biochemical research and should be well able to tackle new and unfamilar problems. The Editors in their Preface (and also in their article in Biochemical Education (Vol. 1, 8, 1972) explain how the book came to be compiled; clearly the Cambridge biochemistry undergraduate is just as vulnerable as his contemporaries elsewhere when exposed to quantitative aspects of the.subject] The advantage to be gained by adoption of the data-handling and problems approach in biochemical teaching, as stressed by Doctors Kerridge and Tipton, cannot be overemphasized. Indeed the approach is as valid now as it was when we first made this observation in 1956 and today surely few teachers of biochemistry would deny its value. The book is well produced with a pleasing type face and clear illustrations: There are inevitably in a volume of this sort a few minor irritations, such as the continued use in the S.I. era of m/l, the terms absorbance and optical density both appearing in the same question, and chromatogram used as a verb. However, the Editors have patently succeeded in their intention to produce more than a collection of questions and answersand the book is a worthy addition to the expanding literature on the quantitative aspects of biochemistry. At £2.60 in paperback the book represents a good buy but publishers who have the temerity t o charge £8.15 for a hardback copy deserve (and surely will get!) the round condemnation of every University Librarian. E.A. Dawes Department of Biochemistry, University of Hull. U.K.
w
Fertilization and its Biochemical Consequences By Alberto Monroy. Pp. 38. Addison-WesleyPublishing Company. 1973 $1.00 (Paperback).
January 1974 Vol. 2 No. 1 i
19
H|
It also has something for the more curious graduate student not specializing in problems connected with fertilization of the animal egg. J.R. Tata
The series of small monographs published as Addison-Wesley Modules in Biology represents a welcome attempt to filla significant gap in scientificcommunication. H o w successful such a venture'is likely to be for biochemical education depends on the selection of topics and authors. The subject of differentiation is attracting increasing attention from molecular biologists and Professor Alberto Monroy is an authority on the biochemical basis of differentiation. It is therefore easy to predict that the 7th "module" on "Fertilization and its Biochemical Consequences" by Professor Monroy is bound to be a success.
In 37 pages Professor Monroy has covered a wide range of phenomena concerning the maturation and the early events following fertilization of the animal egg. The "module" is divided into two parts. The first part describes the morphological and physiological changes taking place after fertilization and the second covers the biochemical changes. The introduction gives a simple definition of "Fertilization" and a very brief but succint summary of the most important events immediately after fertilization. Two major aspects of morphological and physiological changes covered are a) garnets fusion and formation of the zygote nucleus, and b) the structural changes noticeable in the fertilized egg, with particular attention paid to changes in cortical granules, the viteUine membrane and the hyaline layer. The morphological description is adequately supported by illustrations (4 line drawings and 8 photographs). There is an impressive reproduction of a scanning electron microscopic view of the sperm-egg interaction but unfortunately the quality of most photographic reproductions is poor - perhaps due to the necessity of keeping down production costs. In describing the biochemical aspects of fertilization, Professor Monroy very judiciously begins with an account of the process of oogenesis, particularly the elaboration a , d storage of information in the form of DNA, RNA and proteins of the mature egg. The rest of the biochemical coverage largely concerns the activation of stored maternal messenger RNA and the transcription of embryonic nuclear DNA after fertilization. The conclusion drawn is that both these processes occur simultaneously. All the other biochemical changes are extremely briefly covered under "fertilization-dependent metabolic changes" and one wonders whether it would not have been preferable to leave this last bit out altogether. A major criticism of this otherwise fascinating account of fertilization is that it is too narrowly based on Professor Monroy's own interest in the control of protein synttfesis during fertilization of the sea"urchin (and frog) egg. It could be argued that it is wrong to generalize from eichinoderm and frog eggs, which are fertilized and develop independently of maternal influences, to mammalian eggs which are under maternal (and placental) regulation for a considerable time after fertilization. It is also known that, unlike frog and sea urchin eggs which lay down a large enough store of maternal ribosomes to support protein synthesis beyond gastrulation, development of fertilized mammalian eggs is dependent on ribosomal RNA synthesis from the four-cell stage onwards. The disproportionate emphasis on regulation of protein synthesis - albeit most important for differentiation - may give a misleading impression of a minor role played by processes such as control of permeability, membrane function and metabolite gradients during differentiation. These shortcomings should not detract from the lucid style and the authoritative account of regulation of protein synthesis before and after fertilization of the egg. Professor Monroy's "module" should be a valuable adjunct to the standard undergraduate courses in biochemistry and developmental biology.
National Institute for Medical Research, Mill Hill, London, U.K.
Biochemical Reasoning. Numerical Examples for Students Edited by D. Kerridge& K.F. Tipton, W.A. BenjaminInc. Hardback£8.15; Paperback£2.60. The last few years have witnessed the publication of several new books presenting numerical and problem-solving aspects of biochemistry and the initial reaction to Biochemical Reasoning might well be "What, another?" However, the present collection differs from its predecessors by placing greater emphasis on the interpretation of experimental data, providing extensive hints on the solution of the problems and comprehensive answers, while eschewing any formal supporting text on the topics covered. The questions have been constructed, principally from the original literature, by members of the staff of the Biochemistry Department at Cambridge. The book is divided into three sections, the first presenting 57 questions (78 pages), the second (34 pages) giving hints for their solution, and the third (125 pages) proving the detailed answers. An appendix and index complete the work. The questions "fall into five sections, namely, The Structure of Macromolecules (13), Enzymes (20), Respiration and Photosynthesis (5), Microbial Growth and Metabolism (8) and Molecular Genetics and Biosynthesis (11). Within the framework a wide range of experimental topics is covered and a student who, during his course, has worked his way conscientiously through most of them will certainly have a good grasp of the scientific reasoning underlying current biochemical research and should be well able to tackle new and unfamilar problems. The Editors in their Preface (and also in their article in Biochemical Education (Vol. 1, 8, 1972) explain how the book came to be compiled; clearly the Cambridge biochemistry undergraduate is just as vulnerable as his contemporaries elsewhere when exposed to quantitative aspects of the.subject] The advantage to be gained by adoption of the data-handling and problems approach in biochemical teaching, as stressed by Doctors Kerridge and Tipton, cannot be overemphasized. Indeed the approach is as valid now as it was when we first made this observation in 1956 and today surely few teachers of biochemistry would deny its value. The book is well produced with a pleasing type face and clear illustrations: There are inevitably in a volume of this sort a few minor irritations, such as the continued use in the S.I. era of m/l, the terms absorbance and optical density both appearing in the same question, and chromatogram used as a verb. However, the Editors have patently succeeded in their intention to produce more than a collection of questions and answersand the book is a worthy addition to the expanding literature on the quantitative aspects of biochemistry. At £2.60 in paperback the book represents a good buy but publishers who have the temerity t o charge £8.15 for a hardback copy deserve (and surely will get!) the round condemnation of every University Librarian. E.A. Dawes Department of Biochemistry, University of Hull. U.K.