Morphology C
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Morphology C. S. CHADWICK Head, Departmentof Biology George Peabody College for Teachers "Miorphology ... is one of the most as depth, and probably breadth should be the interesting departments of natural history, and first objective. may almost be said to be its very soul." The good general biology course at the (Charles Darwin, The Ori- high school or college level should provide gin of Species.) These two breadth. In such a course the student would be statements, (a) that mor- introduced to those principles and laws which phology is interesting, and are common to all of the fields of biology. Downloaded from http://online.ucpress.edu/abt/article-pdf/17/1/14/14462/4438659.pdf by guest on 30 September 2021 (b) that it is in large part Enough morphology would be taught to pro- the soul of natural history vide the basis for the understanding of func- are sufficient arguments for tion. In considering protoplasm and its or- the inclusion of a healthy ganizational units, the parts of the cell would dosage of morphology in have to be learned. In a sequential study of the biology curriculum. the world of living things, which would fol- / Although the history of low consideration of the cell doctrine, mor- biology has been largely phology would be taught as needed. The the study of the form and structure of student would learn about cell aggregation, organisms, the importance of morphology division of labor between somatic and germ seems now to reside in the fact that it provides cells, specialization of somatic cells, tissue a basis for the understanding of function, formation, organ formation and the organ development, heredity, taxonomy, ecology systems, without having been impressed with and other branches of biology. the fact that these are in the domain of mor- It is to be admitted readily that morphology phology. Even the great principles of struc- alone is not enough, but it must be admitted ture-metamerism, symmetry, cephalization, also that a knowledge of morphology is pre- regional differentiation and the subdivisions of requisite to the understanding of function. the coelom-would become evident without The structure and form of the organism is a pointing up the fact that these are all a part of framework in which and by which life func- the field of morphology. tions are accomplished. Because this is true a knowledge of morphology is indispensable in It would be in the advanced courses for a any study, or in any phase or field of study, biology major that the student would gain of the living organism. depth. In courses in comparative anatomy, and he would The first question the inherently inquisitive embryology, histology cytology student is likely to ask in regard to a thing dig more deeply into the special subject of is, "What is it?" The answer requires a morphology. But even in these courses, func- knowledge of morphology. The next question tion should not be excluded. There is a will likely be, "What is it good for? " or definite, and probably wise, trend towards "WThat does it do? " The answer to these functional anatomy. Instead of requiring stu- requires a knowledge of function. Other dents to learn the name, origin, insertion, ac- questions will likely be, "Where did it come tion, innervation, form, position and blood from?" and "How did it come to be like it supply of each individual muscle in the body, is?" To answer these one has to draw upon he learns muscles as functional groups. Such a knowledge of embryology, evolution, knowledge is more meaningful. In embry- genetics, ecology, etc. ology, in addition to learning the fate of the If the teacher knows only morphology, or germ layers and the successive structures only one of the several fields of biology, he is which develop from them, the student would not likely to satisfy the curiosity of the stu- study gametogenesis, fertilization and . the dent. His training must have breadth as well formation of the zygote, the mechanisms 14 Volume 17, No. 1 MORPHOLOGY 15 which bring egg and sperm together, the Recorder's Report of Discussion on organizers,devices for the nourishmentof the MORPHOLOGY developing individuals, metamorphosis, and the phenomena of hatching and parturition. Morphology, when taken in its broadest To understandembryology one is forced into concept, concerns the study of the form and a study of the hormones,enzymes and genes structure of living organisms.It provides a as they relate to development. In histology basis of interpretationand understandingof and cytology the functional approach also is other aspects of biology, such as those of stressed. physiology, heredity, ecology, taxonomy, evolution and others. directed at biology Much criticismhas been NMorphologymay obtain its chief place of in general and morphology in particularfor importance as a tool by which it forms the Downloaded from http://online.ucpress.edu/abt/article-pdf/17/1/14/14462/4438659.pdf by guest on 30 September 2021 It is said its apparentlyunending terminology. foundation,the superstructureor the building just and rightly so, that we are not content blocks, for the various topics of study which we have to have one big name for a structure, seem to be essential.It may also be important or a half dozen. to have two, or three perhaps as a disciplineitself, leadingto hobby interests the dissection We are criticized for requiring or further pursuitsin anatomy or taxonomy. of endless, smelly, formalin-preservedspeci- mens; for requiringthe students to make too General biology courses in the past have many drawings;for not having enough field- been largely basedon structure,because of the trips; for adheringtoo closely or not closely greater amount of this type of information enough to a textbook, and so ad infinitum. available.The more recent trend has been to emphasizephysiology, as new discoverieshave In leading our students towards a knowl- been made in that field. The general opinion edge of the principles of biology we cannot of those discussingthis point is that there is a exclude morphology, but we can have too definite need for balancebetween these areas. much emphasison certain phasesof this area. Thus, morphology, physiology, ecology and In learning morphology we can have too other phasesof biology, kept in balanceby an much terminology or we can have too little. able teacher, should lead to the better under- In laboratory practice we can require that standing of basic biological principles. The the students make too many drawings,or too real danger lies in making any one subject few; we can require too much dissection or an end in itself, rather than an integrated we can leave some things undissected.We can whole. have too few field trips or too many. We may Some of the principles of morphology put laboratorybefore the lecture, the lecture which are important in the preparation of before the laboratory,or we may carry them biology teachersinclude the following: along together. We may use too many audio- 1. knowledge of organ systems in repre- visual aids, or not enough. We may use a sentative organisms textbook much, little or not at all. We may 2. levels of organization from simple to be guilty of cook-bookery in laboratory in- complex struction, or exhaust ourselveswith verbally- 3. symmetry, metamerism and cephaliza- given instructions.The importantthing is that tion we do not go to any of these extremes, but 4. regional differentiation 5. cells and the division of labor among ratherseek a balance. cells We should seek balance not only in our 6. homology handling of the subject of morphology, but 7. the organismas an end product of hered- seek to balancemorphology content with con- ity and environment 8. morphological evidences of evolution, tent from genetics, taxonomy, ecology, evolu- physiology and taxonomy. tion, physiology and other phases of the field These principles may be projected in sig- of biology. Only in so doing can we hope to nificant courses given as an importantpart of turn out balanced, well-rounded, well-edu- the teacher training program, and for other cated, biology students. knowledge of biology. 16 THE AMERICAN BIOLOGY TEACHER Jaiiiary 1955 Emphasishas been placed on the necessity The methods by which the principles of of a good general biology course of at least morphology may be taught through signifi- one year durationin which there is a balance cant coursesare many and varied.Some prefer of morphology, physiology and other areas to use such approaches to various types of including as many of the fundamentalprinci- subject matter as the following: ples of each as fits the situation. Although a. the functional approach some participantsprefer separatehalf-year or b. the problemapproach quarter courses in botany and zoology, the c. the questionapproach majority preferreda requiredgeneral biology d. the phylogenetic approach course during the first year to be followed Others wish to use combinationsof these aris- by such other coursesas: ing from need. 1. Second Year However all concurred in stressingthe im- Downloaded from http://online.ucpress.edu/abt/article-pdf/17/1/14/14462/4438659.pdf by guest on 30 September 2021 a. Human Physiology portance of the well-trainedteacher. In addi- 2. Third Year tion to teacher preparationthe following at- a. Nature Study, Genetics or Bacteri- tributesseem important: ology 1. adaptability students who wish to gain a fundamental 2. desire for continuedgrowth 3. Fourth Year or GraduateLevel 3. skill in teaching techniques a. ComparativeAnatomy 4. rich experiences b. Embryology and Histology 5. skill in laboratoryand field work c. Taxonomy 6. ability to use wisely such teaching aids d. Plant Morphology such as e. Ecology a. blackboardfor illustrations f. Entomology b. audio-visualaids The need of one or more concurrent or 7.