scholarly journals General morphology of the oral cavity of the Nile crocodile, Crocodylus niloticus (Laurenti, 1768). I. Palate and gingivae

2003 ◽  
Vol 70 (4) ◽  
Author(s):  
J.F. Putterill ◽  
J.T. Soley
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Connective Tissue ◽  
Taste Receptors ◽  
General Morphology ◽  
Histological Features ◽  
Microscopic Features ◽  
Sensory Structures ◽  
Nile Crocodile ◽  
Scanning Electron

The heads of nine 2.5 to 3-year-old Nile crocodiles (Crocodylus niloticus) were obtained from a commercial farm where crocodiles are raised for their skins and meat. The animals from which these specimens originated were clinically healthy at the time they were slaughtered. A detailed description of the macroscopic and microscopic features of the palate and gingivae of the Nile crocodile is presented and the results are compared with published information on this species and other Crocodylia. The histological features are supplemented by information supplied by scanning electron microscopy. Macroscopic features of interest are the small conical process situated at the base of the first two incisors of the maxilla, the distribution of cobbled units on the palate, and the broad dentary shelf forming the rostral aspect of the mandible. Histologically the palate and gingivae did not differ significantly from each other and both regions showed a presence of Pacinian-type corpuscles. Two types of sensory structures (taste receptors and pressure receptors) were identified in the regions examined, both involving modification of the epithelium and the underlying connective tissue.

Comparative Study of the Fine Morphology of Sensory Receptors in Aspidogaster conchicola and Cotylaspis insignis

1972 ◽  
Vol 30 ◽  
pp. 150-151
Author(s):  
Venita F. Allison ◽  
J. E. Ubelaker ◽  
J. H. Martin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Nervous System ◽  
Osmic Acid ◽  
Sensory Receptors ◽  
Transmission Electron ◽  
Sensory Structures ◽  
Fine Morphology ◽  
Scanning Electron

It has been suggested that parasitism results in a reduction of sensory structures which concomitantly reflects a reduction in the complexity of the nervous system. The present study tests this hypothesis by examining the fine morphology and the distribution of sensory receptors for two species of aspidogastrid trematodes by transmission and scanning electron microscopy. The species chosen are an ectoparasite, Cotylaspis insignis and an endoparasite, Aspidogaster conchicola.Aspidogaster conchicola and Cotylaspis insignis were obtained from natural infections of clams, Anodonta corpulenta and Proptera purpurata. The specimens were fixed for transmission electron microscopy in phosphate buffered paraformaldehyde followed by osmic acid in the same buffer, dehydrated in an ascending series of ethanol solutions and embedded in Epon 812.

Light and Scanning Electron Microscopy of Human Spinal Ligaments

1985 ◽  
Vol 55 ◽  
Author(s):  
L.-H. Yahia ◽  
G. Drouin ◽  
C.-H. Rivard
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Connective Tissue ◽  
Idiopathic Scoliosis ◽  
Blood Vessels ◽  
Structural Changes ◽  
Loose Connective Tissue ◽  
Morphological Studies ◽  
Spinal Ligaments ◽  
Scanning Electron

ABSTRACTSpinal ligaments were obtained from normal and scoliotic individuals. Detailed morphological studies were carried out on the yellow, interspinous and supraspinous ligaments by light and scanning electron microscopy. Normal yellow ligaments are mostly constituted of dense elastin fibers with only a few collagen fibers and sparse blood vessels, while in normal interspinous and supraspinous ligaments, the presence of collagen is highly dominant. In the latter structures, the collagen fascicles are characterized by a regular waviness morphology. The fibrils constituting the fascicles appear either parallel or helical with respect to the fascicle axis. Structural changes are observed in the spinal ligaments of patients with congenital as well as idiopathic scoliosis. For yellow ligaments, only slight differences are found between normal and scoliotic specimens. However, alterations in collagen waviness and architecture are observed mainly in the supraspinous ligaments and to a lesser extent in the interspinous ligaments. In addition, increases in the cellularity, loose connective tissue and vessels are found in both forgoing ligaments. These results indicate that the more pronounced scoliosis-related changes occur in ligaments having the farthest distance from the axis of flexion-rotation.

scholarly journals Fine Structure of Maxillary Palps in Adults of Hermetia illucens (Diptera: Stratiomyidae)

2020 ◽  
Author(s):  
M Pezzi ◽  
C Scapoli ◽  
M Bharti ◽  
M J Faucheux ◽  
M Chicca ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sexual Dimorphism ◽  
Hermetia Illucens ◽  
The Family ◽  
Sensory Structures ◽  
First Time ◽  
Maxillary Palps ◽  
Scanning Electron

Abstract A relevant species in waste management but also in forensic, medical, and veterinary sciences is the black soldier fly, Hermetia illucens (Linnaeus; Diptera: Stratiomyidae). An ultrastructural study by scanning electron microscopy (SEM) was conducted for the first time on maxillary palps of both sexes, describing in detail the morphology and distribution of sensilla and microtrichia. The maxillary palps, composed of two segments, show sexual dimorphism in length and shape. In both sexes, the first segment is covered only by microtrichia, but the second one is divided into two parts: the proximal one, covered only by microtrichia, and the distal one containing both microtrichia and sensory structures. These structures include two types of sensory pits and one of chaetic sensilla. Due to sexual dimorphism in palp size, females have a higher number of sensory pits. The sexual dimorphism of palps and the presence and role of sensilla in H. illucens was discussed in comparison to other species of the family Stratiomyidae and of other Diptera. This study may represent a base for further investigations on mouthpart structures of this species, involved in key physiological activities, such as feeding, mating and oviposition.

Scanning electron microscopy of lattice organs in cyprids of the Rhizocephala Akentrogonida (Crustacea: Cirripedia)

1994 ◽  
Vol 72 (6) ◽  
pp. 1018-1026 ◽  
Author(s):  
Peter Gram Jensen ◽  
Jens T. Høeg ◽  
Susan Bower ◽  
Alexey V. Rybakov
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sister Group ◽  
Poor Quality ◽  
Sister Group Relationship ◽  
Sensory Structures ◽  
Lattice Organs ◽  
Almost All ◽  
Scanning Electron

The morphology and disposition of lattice organs, putative sensory structures in the carapace of cyprids, are described with scanning electron microscopy from six rhizocephalan species representing four of the five families in the suborder Akentrogonida: Clistosaccus paguri and Sylon hippolytes (Clistosaccidae), Arcturosaccus kussakini (Duplorbidae), Mycetomorpha vancouverensis (Mycetomorphidae), and Diplothylacus sinensis and Thylacoplethus reinhardi (Thompsoniidae). The disposition of pores and setae on the cyprid carapace is also surveyed. In T. reinhardi, poor quality of the specimens allowed only confirmation that lattice organs are present. Cyprids of all other species except M. vancouverensis have two anterior and three posterior pairs of lattice organs on the carapace, just as in almost all other Cirripedia. Cyprids of C. paguri and S. hippolytes are nearly identical in both general shape, carapace setation, and morphology of the lattice organs. In both species the lattice organs are oval–circular pore fields, except the second pair which is very elongate and match-shaped, a morphology unique to the Clistosaccidae. The similarities in cyprid morphology are interpreted as apomorphies supporting the monophyly of the recently rediagnosed Clistosaccidae. Both thompsoniid species have oval–circular lattice organs, indicating a possible sister-group relationship between the Clistosaccidae and the Thompsoniidae. None of the lattice organs of A. kussakini are oval or match-shaped. In M. vancouverensis there is only a single anterior pair of lattice organs, a probable autapomorphy. But the morphology of the M. vancouverensis cyprid is otherwise very reminiscent of those in the Rhizocephala suborder Kentrogonida, such as in being ornamented with numerous (> 100) carapace setae in no fixed pattern compared with the few (< 80) setae in a fixed disposition seen in the other akentrogonids. In cyprids of all Akentrogonida examined, the lattice organs lack a large terminal pore. By out-group comparison with all other cirripedes and with the Ascothoracida, this is regarded as an apomorphy that supports the monophyly of the Akentrogonida.

Sign in / Sign up

Export Citation Format

Share Document