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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 127 (1972), S. 492-525 
    ISSN: 1432-0878
    Keywords: Spermatozoa ; Drosophila ; Testis ; Fertility ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In Drosophila melanogaster, the cyst cell that surrounds the head region of sperm bundle becomes spheroidal or ellipsoidal and is trapped by the terminal epithelium of the testicular wall during the synchronous coiling of sperm. Extensions of this cyst cell are projected caudally into the interspaces between sperm heads probably to anchor the heads. Coiling of sperm tails is initiated at the head region and proceeds by the progressive retraction of the linear portion from the apical testicular region into the coiled portion at the base. The addition of one turn of coil is accompanied by one full rotation of the sperm bundle. When coiled, normal tails are tightly packed into a hexagonal lattice, and minute tubular structures of about 150 Å in diameter occupy the space between them. Sperm with abnormal tails are separated from those with normal ones and isolated into a separate part of the cyst lumen. Acid phosphatase is involved in the dissolution of the minute tubules for the liberation of sperm from the cyst. Sperm are released leaving the major portion of the cyst cells intact. This portion contains degenerating abnormal tails and the waste products of the individualization process. This detritus is ingested by the terminal epithelium and eventually degenerates.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 124 (1972), S. 479-506 
    ISSN: 1432-0878
    Keywords: Spermatozoa ; Drosophila ; Testis ; Fertility ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A morphogenetic process that transforms spermatids from a syncytial state to a state in which each spermatid is invested in its own membrane, is initiated at the head region of the spermatid bundle and traverses through the entire length of the bundle in the testis of Drosophila melanogaster. This process not only eliminates the syncytial bridges between spermatids but also removes unneeded organelles and the excess parts of the nuclear membrane, nucleoplasm and cytoplasm. It also brings about structural modifications to flagellar elements. The propagation of this process is seen as the caudal movement of a fusiform swelling of the spermatid bundle, 100 μ or more in length. Spermatids are individualized in the basal half of the swelling, whereas they remain syncytial in the apical half. The swelling increases its volume as it accumulates cytoplasmic debris while traversing the sperm bundle, from about 15 μ in maximum diameter in the basal testicular region to as large as 30 μ at the apical end where it becomes a bag of wastes. A variation of the process in a mutant stock which is known to inactivate up to half of the products of meiosis is briefly described. The morphological change of interspermatid bridges prior to the individualization is also reported.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
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