Abstract:
:Spermatogenesis discontinues during both adult reproductive diapause and quiescence in the flightless males of Omorgus freyi. During both types of dormancy, spermatogenesis discontinuity is a dynamic process involving an uninterrupted supply of primary spermatocytes that undergoes partial development and lyses before spermatozoa can be formed. Notwithstanding this common feature, the pattern of discontinuity differs between the two kinds of dormancy. During reproductive diapause, spermatozoa and late spermatids are the first cells that lyse; after diapause break, spermatozoa are produced anew. During quiescence, in contrast, the first indication of discontinuity is the degeneration of late primary spermatocytes; spermatozoa apparently remain intact for a while but eventually degenerate as well. Therefore, males returning to sexual activity after a short period of quiescence may still have spermatozoa capable of fertilization. However, following a long period of quiescence, spermatozoa will be absent and must be produced anew, as in postdiapausing males. The existence of two different patterns of spermatogenesis discontinuity may indicate that each is controlled differently by the endocrine system, in response to the different environmental conditions inducing quiescence or diapause. Dual control of discontinuity may contribute to the high reproductive potential of these flightless beetles, under unpredictable and extreme desert conditions. © 1993 Wiley-Liss, Inc.
journal_name
J Morpholjournal_title
Journal of morphologyauthors
Friedländer M,Scholtz CHdoi
10.1002/jmor.1052180309subject
Has Abstractpub_date
1993-12-01 00:00:00pages
347-358issue
3eissn
0362-2525issn
1097-4687journal_volume
218pub_type
杂志文章abstract::Bone is a dynamic tissue adapting to loading according to "Wolff's law of bone adaptation." During very early life, however, such a mechanism may not be adequate enough to adapt to the dramatic change in environmental challenges in precocial species. Their neonates are required to stand and walk within hours after bir...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20548
更新日期:2016-07-01 00:00:00
abstract::Astroblepidae or "climbing catfishes" encompass a single genus of species living in high altitude rivers in the Andes of South America. They are characterized by a specialized head morphology closely resembling their better known, widely radiated sister family Loricariidae, or armored suckermouth catfishes. Existent d...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20169
更新日期:2013-10-01 00:00:00
abstract::Newly metamorphosed Kenyan reed frogs, Hyperolius viridiflavus ferniquei, are able to regenerate amputated digits. The terminal digital pad is also completely reformed. Differentiation of the regenerating digital pad was studied by scanning electron microscopy. External differentiation of the digital pad began late in...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051530305
更新日期:1977-09-01 00:00:00
abstract::Detailed descriptions of mammalian sperm morphology across a range of closely related taxa are rare. Most contributions have been generalized descriptions of a few distantly related mammalian species. These studies have emphasized a generalized ungulate sperm morphology, but have not underscored several important morp...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10297
更新日期:2005-02-01 00:00:00
abstract::Statoblasts of five higher phylactolaemates were compared morphologically. As a result, they were divided into two groups: Group I comprising Lophopus crystallinus, Lophopodella carteri, and Pectinatella gelatinosa, and Group II comprising Pectinatella magnifica and Cristatella mucedo. These two groups are thought to ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051650203
更新日期:1980-08-01 00:00:00
abstract::The apical area of larvae of four primitive pulmonate species was investigated by means of serial ultrathin and light microscope sections. Cephalic sensory organs (CSOs) were found in the larvae of Onchidium cf. branchiferum (Onchidiidae) and Laemodonta octanfracta (Ellobiidae), while no trace of the organ was present...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1076
更新日期:2002-01-01 00:00:00
abstract::The oral dentition and type and number of taste buds (TB) on the lips and in the oropharyngeal cavity were compared by means of SEM in 11 species of cardinal fishes (Apogonidae) belonging to five genera. The occurrence of a dense cover of skin papillae on the lips of some species (e.g., Apogon frenatus), as well as di...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10186
更新日期:2004-03-01 00:00:00
abstract::The structure of the thumus in adult specimens of a marine teleost, the cling fish Sicyases sanguineus, has been studied by light and transmission electron microscopy. Most cling fishes have an outer thymus located beneath the opercular epithelium. A few of them, however, have a large inner thymus besides a poorly dev...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051770103
更新日期:1983-07-01 00:00:00
abstract::A reduction in free ribosomes and increases in rough endoplasmic reticulum and Golgi complexes in follicle cells during oogenesis suggest their involvement in supplying precursor material for synthesis of the vitelline and chorionic membranes of the ichneumonid parasitoid Campoletis sonorensis. The inner region of the...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051740207
更新日期:1982-11-01 00:00:00
abstract::Many studies in the genus Poecilia have focused on reproductive and genetic characteristics of Poecilia formosa, the Amazon molly, and its sympatric species P. latipinna and P. mexicana. The research literature of Poecilia dentition has been limited to general tooth morphology. Essentially absent are comparative analy...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199903)239:3<271::AID-JMOR
更新日期:1999-03-01 00:00:00
abstract::The skull of neotenic individuals of the Alpine Newt Triturus alpestris from the locality Drakolimni (Greece) is described on the basis of models made from magnified serial frontal sections. In order to recognize features associated with neoteny and paedomorphosis, the results were compared with normal development of ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199611)230:2<187::AID-JMOR
更新日期:1996-11-01 00:00:00
abstract::The posterior half of the channel catfish intestine has a similar histological organization to that of other teleost fishes. This region is organized into a muscosa, a submucosa, a double layered muscularis and a serosa. A "stratum compactum" of dense connective tissue was confirmed for the submucosa. In its histology...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051450405
更新日期:1975-04-01 00:00:00
abstract::Zebra Finches (Taeniopygia guttata) are the most commonly used laboratory songbird species, yet their embryological development has been poorly characterized. Most studies to date apply Hamburger and Hamilton stages derived from chicken development; however, significant differences in development between precocial and...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20165
更新日期:2013-10-01 00:00:00
abstract::The overall anatomy of Neodasys as well as data for hemoglobin-containing cells are described. Hemoglobin-containing cells are shown to be mesodermal specializations constituting approximately 14% of the animal's total body volume (4.87 ± 104 μl). These globular cells (10-14 μm) are situated in two longitudinal rows, ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051750106
更新日期:1983-01-01 00:00:00
abstract::Iridescent butterfly scales are structurally colored, relying upon the interaction of light with detailed architecture to produce their color. In some iridescent scales, the reflective elements are contained within the body of the scale and come in two basic forms, lattices that produce diffraction colors (analogous t...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052020106
更新日期:1989-10-01 00:00:00
abstract::The ultrastructure of five epithelial cellular types is described. (1) Absorptive-storing cells possess a striated border and accumulate lipids and glycogen. They also contain an apical multivesicular complex and numerous membrane-bound PAS-positive granules of unknown significance. (2) Zymogenic cells contain numerou...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052020203
更新日期:1989-11-01 00:00:00
abstract::Adult female white-footed mice, Peromyscus leucopus, were exposed to long (LP) or short (SP) photoperiods for 6 weeks (experiment I). Another group of animals was kept for 6 weeks in SP, then injected SC with 30 micrograms prolactin twice daily for 2, 3, 4, or 6 days (experiment II). Ovaries from the mice in both expe...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051760211
更新日期:1983-05-01 00:00:00
abstract::The wall of the asymmetrical saclike lungs of the fishes Polypterus and Erpetoichthys consists of several functionally different tissue layers. Their lumen is lined by a surface epithelium composed of (1) highly attenuated cells, termed pneumocytes I; (2) pneumocytes II with lamellar bodies, presumably indicating surf...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052010206
更新日期:1989-08-01 00:00:00
abstract::Data describing segmental masses and moments of inertia (MOI) of limb segments are required for inverse dynamic calculations. In horses, these values are usually calculated using regression equations that have been developed from a limited number of horses representing a small number of breeds. The objective of the pr...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20829
更新日期:2018-07-01 00:00:00
abstract::The strongly modified mode of development of the small and brooding galeommatoid bivalve Lasaea adansonii (Gmelin, 1791) [syn. Lasaea rubra (Montagu, 1803)] has been studied by means of transmission and scanning electron microscopy and by fluorescent staining of the muscular system and of two neurotracers, FMRFamide a...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10623
更新日期:2008-06-01 00:00:00
abstract::A statistical and functional relationship between neural canal anatomy and locomotor mode is demonstrated in living marine mammals of the Order Carnivora. This relationship is interpreted to be the result of differential innervation and territory of musculature involved in generating the six locomotor patterns analyze...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052140311
更新日期:1992-12-01 00:00:00
abstract::Based on light microscopic observations, nerve pathways are described for the first time in the praesoma of a species of the Echinorhynchidae. The pathways are described for 18 nerves, 8 paired and 2 single, which originate from the cerebral ganglion and a post-ganglionic cell and terminate in the body wall musculatur...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052010306
更新日期:1989-09-01 00:00:00
abstract::Interspecific variations in rhabdom structure between various oplophorid shrimps are described and the differences are related to the light environment at different depths within the mesopelagic zone. The ultrastructure of the distal rhabdom in these species is described for the first time. Quantitative measurements s...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10103
更新日期:2003-07-01 00:00:00
abstract::The prowfish, Zaprora silenus, is the sole member of the family Zaproridae. It is a large, relatively elongate species with a robust head and body, and it feeds primarily on jellyfishes. Although the larvae and juveniles are pelagic, the adults are demersal, and the species is widely distributed from Southern Californ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20168
更新日期:2013-10-01 00:00:00
abstract::The common snook, Centropomus undecimalis, was induced to ovulate using a time-release, GnRH analogue. Ovulation occurred the afternoon or evening the day after hormone administration. The time of ovulation was established within half an hour. At ovulation, three fish per time-group were divided into 0, 6, 12, 18 hr a...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20652
更新日期:2017-04-01 00:00:00
abstract::In the present investigation the right intracranial portion of the trochlear nerves and dorsal oblique muscle of the right ocular globe were removed from six adult dogs and analyzed by light and electron microscopy. Unmyelinated fibers were observed in the analyzed nerves. The number, diameter, area, and density of my...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10271
更新日期:2004-12-01 00:00:00
abstract::An ultrastructural study of the ovary of the sessible jellyfish, Haliclystus octoradiatus, indicates that it is fundamentally different from that of other scyphozoans and is the most structurally complex within the class. Oocytes develop within a series of spherical, sac-like ovarian follicles consisting of an enlarge...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052180210
更新日期:1993-11-01 00:00:00
abstract::Amphisabenia is a group of squamates adapted for a fossorial lifestyle. The skull is the animal's the main digging tool, and can present one of four principal shapes. The shovel-headed shape is considered to be the most specialized for digging. The South American genus Leposternon presents a shovel-headed morphotype, ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20899
更新日期:2018-11-01 00:00:00
abstract::A hitherto unknown sensillum type, the "intracuticular sensillum" was identified on the dactyls of the walking legs of the shore crab, Carcinus maenas. Each sensillum is innervated by two sensory cells with dendrites of "scolopidial" (type I) organization. The ciliary segment of the dendrite is 5-6 μm long and contain...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052040311
更新日期:1990-06-01 00:00:00
abstract::Barnacle cypris larvae show high morphological variation in the organs used in search of and attaching to a substratum. This variation may represent adaptation to the habitat of the species. Here, we studied SEM level morphologies of cypris antennular sensory and attachment organs in a deep-sea vent endemic species (N...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20522
更新日期:2016-05-01 00:00:00