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  • 1
    Electronic Resource
    Electronic Resource
    Heteromorphic homologous chromosomes in three species of Pseudotrimerotropis (Orthoptera: Acrididae) (1923)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 38 (1923), S. 19-63 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050380103
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  • 2
    Electronic Resource
    Electronic Resource
    The contractile vacuole of paramecium multimicronucleata (1935)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 58 (1935), S. 555-571 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Each contractile vacuole system of Paramecium multimicronucleata is made up of a number of components, some temporary and others permanent. The contracting vacuole with its membrane is a temporary structure as are the vesicles which fuse to form it. The vacuole discharges its contents to the exterior leaving a vestige closing the pore. The pore, with its discharging tubule and the feeding canals are permanent cell organelles. The feeding canals end in injection tubules which extend up to the pore. The vesicles, which later fuse to form the vacuole, are formed at the proximal end of the injection canals, leaving a membrane closing the canal, much as a food vacuole is formed at the gullet. The canal-fed contractile vacuole of Paramecium is very similar to the vesicle-fed vacuole of Euplotes both as to its origin and its fate. The Nassonov homology is rejected.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050580209
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  • 3
    Electronic Resource
    Electronic Resource
    The effect of ultracentrifuging on Paramecium, with special reference to recovery and macronuclear reorganizationAided by a grant from the Rockefeller Foundation for the study of cellular biology. (1937)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 61 (1937), S. 27-49 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Paramecium caudatum becomes much elongated upon centrifuging at 21,000 times gravity. The chromatin is sometimes forced from the achromatic matrix of the macronucleus. The materials in the cell are redistributed according to their relative specific gravities as follows: At the centrifugal end of the cell, crystals, layer of fluid, micronucleus and macronuclear chromatin, food vacuoles and neutral red inclusions, achromatic matrix of the macronucleus, endoplasm with large clear alveoli, and fat, at the centripetal end of the cell. The contracting vacuole is displaced sometimes but not the feeding canals or pore. In some cases the crystals, micronucleus and macronuclear chromatin may be extruded from the cell. Animals which survive centrifuging regain their usual shape and the disturbed materials return to their usual distribution rapidly. Sometimes the crystals remain in large compact masses and are so passed to the daughter cells upon fission. The two components of the macronucleus do not fuse the macronuclear chromatin regenerates an achromatic matrix, and division is somewhat delayed. The old macronuclear matrix persists over a long time and sometimes interferes with division. Animals which have no micronucleus may survive and divide, but no amicronucleate races have been established. Apparently macronuclear chromatin is necessary for the survival and division of P. caudatum; in the absence of the macronuclear chromatin no replacement occurs from the micronucleus. The membrane of the contracting vacuole is temporary.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050610103
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  • 4
    Electronic Resource
    Electronic Resource
    The multiple chromosomes of Paratylotropidia brunneri Scudder (Orthoptera: Acrididae)Aided by grant from the rockefeller foundation for work on cellular biology. (1938)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 63 (1938), S. 289-299 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: There are 19 chromosomes in diploid cells of male Paratylotropidia brunneri; of these, four are V-shaped multiples. There are twenty chromosomes in diploid cells of females; of these, four are V-shaped multiples. If the two arms of each multiple are counted as separate chromosomes, we have the usual number of chromosomes for the Acrididae, i.e., twenty-three in male and twenty-four in female.There are nine chromosomes in the first spermatocyte divisions: seven tetrads, one octad and a decad. The latter is made up of the accessory chromosome associated with an octad.One of the V-shaped multiples in the male is limited to that sex. The homologue of one of the dyads of which it is composed is a free dyad, the homologue of the other forms a V-shaped multiple with the accessory chromosome. The V-shaped multiple limited to the male shows differential heteropycosis in the prophases of the first spermatocyte. There is evidence that its homologous parts are isolated from each other as far as crossingover is concerned.A study of the first maturation division of the heterogametic sex is essential for the identification of the sex chromosome.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050630206
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  • 5
    Electronic Resource
    Electronic Resource
    Pigmentation changes in tadpoles of Rana pipiens following centrifugation during the early gastrulaAided by a grant from the rockefeller foundation for work on cellular biology. (1938)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 63 (1938), S. 477-489 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Centrifuging the eggs of Rana pipiens in the early gastrula stage prevents the formation of the hypophysis in some of the tadpoles. The absence of the melanophorotropic hormone normally secreted by the hypophysis seems to be responsible for the contraction of the pigment cells. In addition, there are actually fewer pigment cells present in both the dermal and epidermal layers of the light tadpoles than there are in the controls. The paleness, therefore, of the tadpoles seems to be due to both a contraction of the pigment cells present and to an actual reduction in their number. The failure of the hypophysis to develop was brought about by centrifuging at an earlier stage in development of the embryo than in previous extirpation studies. The effects produced by centrifuging that are responsible for the failure of the hypophysis to develop are unknown. However, it is suggested that interference in some way with the presumptive hypophysis-forming tissue has resulted in an inactivation of its inductive potencies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050630304
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  • 6
    Electronic Resource
    Electronic Resource
    Changes in the nuclei of differentiating endoderm cells as revealed by nuclear transplantationThis investigation was supported in part by a research grant from the National Cancer Institute of the National Institutes of Health, United States Public Health Service, and in part by an institutional grant from the American Cancer Society. (1957)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 100 (1957), S. 269-311 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051000204
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  • 7
    Electronic Resource
    Electronic Resource
    The origin and early differentiation of the egg chamber of Drosophila melanogasterThis research was supported by the U. S. Public Health Service grants 2-F2-CA-18,847 and GM 9694, the National Science Foundation grant GB 4891, and the American Cancer Society grant E408. The authors wish to express their appreciation to Mrs. Elizabeth T. Stump for her conscientious assistance, and to Mr. E. John Pfiffner for preparation of the inked drawings. (1966)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 119 (1966), S. 283-303 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The egg chamber of Drosophila melanogaster consists of 16 interconnected cells surrounded by a monolayer of follicle cells. Each 16 cell cluster (from which the oocyte and 15 nurse cells differentiate) arises within the germarial region of an ovariole. To study the ultrastructure of the early stages in the formation and differentiation of egg chambers, a three dimensional reconstruction was made from serial thin sections through a germarium from a 24-hour old, virgin female. The germarium was found to be subdivided into three regions: (1) The mitotically active area where clusters of 16 cells originate from a series of cystocyte divisions, (2) the region where these cells interact with mesodermal cells, and (3) the region where the germarial cyst is transformed into the first egg chamber in the vitellarium. Since cystocytes were found to decrease in size with each division, the possibility exists that cell size may determine when the divisions cease. Models are presented which mimic with varying degrees of success the developmental changes the germarial cells undergo with time. Hypothesis are developed to explain why stem line oogonia are restricted to the anterior portion of the germarium, why mesodermal cells first interact with cystocytes in region 2, and why the oocyte is oriented posteriorly. The nuclear differentiations of the component cells of the chamber are described and correlated with observed differences in radiosensitivity. Symbionts were observed in the germaria of several strains of Drosophila, and the bearing of these findings upon nutritional studies is discussed.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051190303
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  • 8
    Electronic Resource
    Electronic Resource
    A comparative investigation of neuroglia in representative vertebrates: A silver carbonate studyThis investigation was supported by Public Health Service Research grant 1-F1-GM-22,665-01 (Pre-Doctoral fellowship) from the National Institutes of Health and General Research Support Grant 320002 of the United States Public Health Service. (1966)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 119 (1966), S. 435-465 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The phylogenetic development of neuroglia (astrocytes, oligodendrocytes) was investigated in homologous cortical and subcortical forebrain regions of selected vertebrates. Microglia were not considered in the current study.Four to seven brains from each species were used. Scharenberg's modification for astroglia of del Rio Hortega's silver carbonate technique was used. The analysis of neuroglia cells was based on (1) the characteristic cellular morphology found in each species, (2) a comparison of the selected regions in each animal, (3) the interrelationships of astrocytes and their relations to neurons, blood vessels, and oligodendrocytes.The predominant type of neuroglia found in the fish, frog, and lizard was the ependymal cell; however, non-ependymal glial cells were also present. The bird represented a transitional phylogenetic stage from a predominance of ependymal glial to a predominance of non-ependymal glia. A progressive increase in the morphological relationships of glial cell bodies and processes to neurons was found with ascension of the phylogenetic scale from fish through primate.Interrelations were observed between adjacent astrocytic processes and cell bodies, and between astrocytes and oligodendrocytes. The processes of adjacent glial cells also appeared to show an increase in thickness at the point of approximation. A variety of astrocytes were observed ranging from small, round-oval shaped cells to large polygonal or stellate forms. Variations in the number of astrocytic processes, their thickness, and degree of secondary branching were described, and their possible functional significance was discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051190405
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  • 9
    Electronic Resource
    Electronic Resource
    Morphological, ultrastructural, histochemical and electrophoretic studies on the venom system of Nasonia vitripennis walker (hymenoptera: Pteromalidae) (1969)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 127 (1969), S. 177-203 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The venom system of Nasonia vitripennis is well-developed and composed of an unbranched acid gland and associated reservoir. Fine-structural, histochemical and electrophoretic studies indicate that the venom is produced by two protein-secreting epithelia. The bulk of the venom is synthesised in the columnar cells of the acid gland and discharged via “vesicular organelles” and the efferent ductular system into the lumen of the reservoir. The acid gland also contains squamous chitogenous cells, situated either around the central lumen or interposed between the bases of the columnar cells. Once within the reservoir, the venom is probably activated by enzymatic secretions from the reservoir secretory cells. Each of these cells has a “vesicular organelle” but, in contrast to the columnar cells of the acid gland, the cytoplasm contains a preponderance of free ribosomes, and protein segregation apparently occurs outside the Golgi complexes.The venom is expelled through the efferent discharge duct by muscular contractions, which open the duct lumen and bring it into contact with the funnel of the ovipositor. Excessive distortion of the duct is prevented by a massive ventral ligament.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051270205
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  • 10
    Electronic Resource
    Electronic Resource
    The cytology of the vitellogenic stages of oogenesis in Drosophila melanogaster. I. General staging characteristics (1969)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 128 (1969), S. 427-441 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The cytology of the vitellogenic stages in the development of the oocyte of Drosophila melanogaster has been studied using whole mounts and sections of plastic-embedded ovaries and single egg chambers for light microscopy and cytochemistry. The migrations, changes in morphology, and synthetic products of the follicle cells are described as a function of developmental stage. The follicle cells synthesize the egg coverings, the vitelline and chorionic membranes, and elaborate the micropyle and dorsal chorionic appendages. The changing structure of the nurse cell nucleus and changes in organelle composition of its cytoplasm are described. The nurse cells synthesize ribosomes, lipid droplets, and mitochondria. These components pass through the ring canal system into the oocyte, which increases in volume some 200,000 times during its 78 hours of development.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051280404
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