Abstract:
:The ultrastructure of the adenohypophysis (AH) in the larval anadromous sea lamprey, Petromyzon marinus L., was examined. The AH is subdivided into three regions, the pro-, meso-, and meta-AH. Cells of the nasopharyngeal stalk extend directly beneath the pro- and meso-AH to form the ventral surface of the gland. Some cells in the pro- and meso-AH are arranged into small follicles. Each region of the AH is characterized by a single granulated (secretory) cell type. Granulated cells constitute 80-90% of the pro-AH and contain secretory granules that range from 800 to 2400 A in diameter. Only 10-20% of the cells in the meso-AH are granulated and they contain much smaller secretory granules (400 to 1250 A diameter) than those in the pro-AH. Granulated cells constitute 80-90% of the meta-AH and contain only a few secretory granules, ranging from 1000 to 2500 A in diameter, and many vesicles containing either a loose flocculent or dense granular material. Non-granulated (stellate) cells are found in all regions. They are characterized by their long cell processes, abundant cytoplasmic filaments, and variable electron density. The appearance of organelles in these cells suggests they are nonsecretory. They may play a role in maintaining the structural integrity of the gland and the regulation of granule release in the pro-AH. Two types of nongranulated cells make up 80-90% of the meso-AH. Type I are stellate cells, type II may be undifferentiated cells. The functional significance of the secretory cells in the larval AH is discussed.
journal_name
J Morpholjournal_title
Journal of morphologyauthors
Wright GMdoi
10.1002/jmor.1051760306subject
Has Abstractpub_date
1983-06-01 00:00:00pages
325-39issue
3eissn
0362-2525issn
1097-4687journal_volume
176pub_type
杂志文章abstract::During epidermal differentiation in mammals, keratins and keratin-associated matrix proteins rich in histidine are synthesized to produce a corneous layer. Little is known about interkeratin proteins in nonmammalian vertebrates, especially in reptiles. Using ultrastructural autoradiography after injection of tritiated...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10181
更新日期:2004-02-01 00:00:00
abstract::Head structures of the leaf mining larva of the chrysomelid species Podagricomela shirahatai are described and illustrated. Internal and external structures were reconstructed three dimensionally based on image stacks obtained with microcomputed tomography. The larval head is characterized by prognathism, a dorsoventr...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20352
更新日期:2015-04-01 00:00:00
abstract::Light and electron microscopic examination demonstrated two types of non-endocrine agranular cells, cavity boundary cells and stellate cells, in the adenohypophysis of the South American lungfish, Lepidosiren paradoxa. The cavity boundary cells line the hypophyseal cleft and diverticulum and display few microvilli, oc...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052070109
更新日期:1991-01-01 00:00:00
abstract::Amphisbaenians are fossorial, predominantly limbless squamate reptiles with distinct cranial shapes corresponding to specific burrowing behaviors. Due to their cryptic lifestyles and the scarcity of museum specimens, little is known of their intraspecific variation, particularly regarding cranial osteology. This repre...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20564
更新日期:2016-09-01 00:00:00
abstract::Exceptional variability in the shell of the pancake tortoise Malacochersus tornieri, both in the keratinous surficial scutes and the underlying bones, in addition to its remarkably fenestrated bony shell are unique among tortoises. Based on 14 individuals of different sizes and ages, the observed variation in M. torni...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20640
更新日期:2017-03-01 00:00:00
abstract::The usual pigmentation pattern in mammalian skin consists of fixed melanocytes in the basal layer of the epidermis, supplying keratinocytes with melanosomes. We observed that the glabrous skin (rhinaria and footpads) of dogs deviates from this pattern. In dogs, melanocytes are found in both the dermis and epidermis. T...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20842
更新日期:2018-08-01 00:00:00
abstract::The objectives of this research were to investigate the morphology of the thoracic skeleton and muscles of the mosquito, Culiseta inornata (Williston). The results are presented in 25 text figures and descriptions of each skeletal part and muscle. Undescribed exoskeletal structures are the postmediotergite, intersegme...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051530308
更新日期:1977-09-01 00:00:00
abstract::The medaka, Oryzias latipes, is a model organism in experimental biology. Its ontogeny and osteology have been studied frequently, but no detailed description of its cranial anatomy exists. Based on manual dissections, histological slide sections, and 3D-reconstructions, we describe the anatomy of the jaw apparatus of...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10746
更新日期:2009-09-01 00:00:00
abstract::Zambian common mole-rats are subterranean rodents that live in families with only one female breeding. Her offspring remain in the parental nest and do not reproduce. Behavioral experiments (Burda, '95) demonstrated that their apparent "sterility" is based on incest avoidance and individual recognition of family membe...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/(SICI)1097-4687(199807)237:1<33::AID-JMOR3
更新日期:1998-07-01 00:00:00
abstract::Nuclear and cytoplasmic volume changes as well as the elimination of residual spermatid cytoplasm were investigated in the red-ear turtle (Pseudemys scripta) and the rooster (Gallus domesticus). Nuclei of newly formed spermatids which were originally centrally located became eccentrically located within the cell in bo...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051980110
更新日期:1988-10-01 00:00:00
abstract::Recent molecular phylogenies conflict with traditional scleractinian classification at ranks ranging from suborder to genus, challenging morphologists to discover new characters that better agree with molecular data. Such characters are essential for including fossils in analyses and tracing evolutionary patterns thro...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10899
更新日期:2011-01-01 00:00:00
abstract::Oribatida are one of the main groups of Acari comprising mostly important decomposers in soils. Most species are particle feeders, an exceptional mode of nutrition in Arachnida. Hence, their feeding organs, the gnathosoma, are of special functional interest. We studied nearly all components using scanning and transmis...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10971
更新日期:2011-09-01 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 phylogenetic position of the Ectoprocta within the Lophotrochozoa is discussed controversially. For gaining more insight into ectoproct relationships and comparing it with other potentially related phyla, we analysed the myoanatomy and serotonergic nervous system of adult representatives of the Phylactolaemata (Pl...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.11006
更新日期:2012-01-01 00:00:00
abstract::This study examines the morphology of sporadic congenital microphthalmia in 1-day-old chicks, with particular emphasis on the neural retina. On the basis of the size of the eyeball it is possible to classify microphthalmia into two groups, severe and mild. In severe microphthalmia (less than 5 mm in equatorial diamete...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051990102
更新日期:1989-01-01 00:00:00
abstract::Pheromone systems from seven species of noctuid are examined. Much of the structure of scales from the wings and/or the abdomen is interpreted as a modification for secretion or release of a pheromone. Scales with an extremely complex surface provide a large evaporation surface, while those connected to secretory cell...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051460107
更新日期:1975-05-01 00:00:00
abstract::The olfactory system of the pigeon (Columba livia) was examined. Our electrophysiological and experimental neuroanatomical (Fink-Heimer technique) data showed that axons from the olfactory bulb terminated in both sides of the forebrain. The cortex prepiriformis (olfactory cortex), the hyperstriatum ventrale and the lo...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051580105
更新日期:1978-10-01 00:00:00
abstract::Among egg-brooding hylid frogs there is much interspecific variation in the degree of development of the young at hatching. In certain species of Gastrotheca the eggs hatch into free-living tadpoles, whereas in others (and in the genera Amphignathodon, Cryptobatrachus, Stefania and Hemiphractus) the eggs hatch directl...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051820102
更新日期:1984-10-01 00:00:00
abstract::The Puerto Rican tree frog, Eleutherodactylus coqui, has internal fertilization and direct development on land. In light of these reproductive adaptations, the events of fertilization and early development were studied. Cytological examination of just-fertilized eggs showed that sperm entry is restricted to about 10% ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051930208
更新日期:1987-08-01 00:00:00
abstract::The chimaeroid holocephalian fishes are distinguished among extant chondrichthyans by the possession of three pairs of tooth plates, evergrowing and partially hypermineralized, that are not shed and replaced like the teeth of living elasmobranchs. Although derivation of the chimaeroid tooth plate from the fusion of me...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052220108
更新日期:1994-10-01 00:00:00
abstract::The theory of Kukalova-Peck ('78) is examined and rejected except for the hypothesis of the partially pleural origin of wings. Data suggest that the arthropods ancestral to insects left the water, and that movable precursors of the wings, possibly exopodites, were immobilized and fused with the tergum to form part of ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051680309
更新日期:1981-06-01 00:00:00
abstract::We investigated if and how the inner ear region undergoes similar adaptations in small, fossorial, insectivoran-grade mammals, and found a variety of inner ear phenotypes. In our sample, afrotherian moles (Chrysochloridae) and the marsupial Notoryctes differ from most other burrowing mammals in their relatively short ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20391
更新日期:2015-08-01 00:00:00
abstract::Motor units of the medial gastrocnemius (MG) and the single lateral gastrocnemius/soleus (LG/S) muscles of the opossum (Didelphis virginiana) were found to have uniformly slow contraction times relative to homologous muscles of the cat. Though a broad range of peak tetanic tensions was found among motor units from bot...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051810305
更新日期:1984-09-01 00:00:00
abstract::All developmental stages of Tanystylum bealensis are described. This is the first complete developmental series of a pycnogonid species collected from a natural, rather than a laboratory-reared population. Development proceeds through a series of nine instars from egg to adult, with major defining characteristics of t...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10402
更新日期:2006-03-01 00:00:00
abstract::The morphology of the upper, lower, and pharyngeal jaws is very similar among American cichlids. Common conditions are: (1) the presence of a premaxillary dentigerous arm shorter than the ascending arm (exceptions are Astronotus, Cichla, and Crenicichla semifasciata), (2) a narrow coulter area; in contrast, a broad co...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1052170102
更新日期:1993-07-01 00:00:00
abstract::The latest research on direct developing caecilian and anuran species indicate presence of only one generation of taste organs during their ontogeny. This is distinct from indirect developing batrachians studied thus far, which possess taste buds in larvae and anatomically distinct taste discs in metamorphs. This stud...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.20544
更新日期:2016-07-01 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::Blood vessels in Nereis japonica were studied by electron microscopy. It was found that blood vessels regardless of location were similar in the basic organization of the basal lamina and the usual presence of collagen fibrils on the vessel wall. Differences arise, depending on whether the outside of the basal lamina ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051440207
更新日期:1974-10-01 00:00:00
abstract::Complete postorbital bars, bony arches that encompass the lateral aspect of the eye and form part of a circular orbit, have evolved homoplastically multiple times during mammalian evolution. Numerous functional hypotheses have been advanced for postorbital bars, the most promising being that postorbital bars function ...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.10334
更新日期:2005-06-01 00:00:00
abstract::The ventral surface of the most proximal tarsomere of each mesothoracic leg of the female black fly, Simulium venustum Say, bears approximately 60 bifurcate sensilla. Externally, a sensillum appears as a hair set into an asymmetric socket and with the distal tip flattened into two flared lobes. A single pore opens int...
journal_title:Journal of morphology
pub_type: 杂志文章
doi:10.1002/jmor.1051650102
更新日期:1980-07-01 00:00:00