The ultrastructure of the cuticle of the nematode Syphacia obvelata (Rudolphi, 1802). IV. The cuticle associated with the female excretory pore, vulva, and vagina vera

1974 ◽  
Vol 52 (2) ◽  
pp. 245-250 ◽  
Author(s):  
T. A. Dick ◽  
K. A. Wright
Keyword(s):  
Internal Pressure ◽  
Excretory Pore ◽  
Body Wall ◽  
The Body ◽  
Muscular System ◽  
Cortical Zone ◽  
Syphacia Obvelata ◽  
Initial Force

The cuticle forming the excretory pore complex and the vulva and vagina vera in female Syphacia obvelata is formed by body wall cuticle. The nature of the cuticle surrounding the excretory pore and forming the bladder, and tile absence of a muscular system to control the complex suggest that internal pressure (probably hydrostatic) is the generating force for fluid expulsion. The lumens of the vulva and vagina vera are lined by and continuous with the cortical zone of the body wall cuticle. The lumens of both the vulva and vagina vera are tetraradiate. The arrangement of the cuticle at the proximal end of the vagina vera allows for a mechanical means of ejecting eggs (the functional ovijector). The initial force to move eggs up to the ovijector is from the muscles surrounding the vagina vera.

The ultrastructure of the cuticle of the nematode Syphacia obvelata (Rudolphi, 1802). II. Modifications of the cuticle in the head end

1973 ◽  
Vol 51 (2) ◽  
pp. 197-202 ◽  
Author(s):  
T. A. Dick ◽  
K. A. Wright
Keyword(s):  
Body Wall ◽  
Buccal Capsule ◽  
The Body ◽  
Head Region ◽  
Limited Region ◽  
Structural Role ◽  
Mouth Cavity ◽  
Median Zone ◽  
Syphacia Obvelata ◽  
Somatic Muscles

The head region of the pinworm Syphacia obvelata (Rudolphi, 1802) has been examined to determine the nature of modification of the cuticle responsible for, or associated with, lips and buccal capsule, cephalic papillae and amphids, cephalic inflations, and cervical alae. The median zone of the cuticle was found to be the most modified and variation in the extent and distribution of striated material is compatible with its proposed structural role. The variations found are probably related to compensation for stresses that may develop in the cuticle during the complex movements of the head end. Lips are only inconspicuous expansions of the body wall cuticle, while esophageal cuticle is strikingly different in appearance. It is proposed to refer to all regions of the mouth cavity bounded by both the lips and esophagus as the buccal capsule while only the limited region bounded by body wall cuticle may be referred to as stoma. A mechanism involving three groups of intrahypodermal cytoskeletal filaments attached to the tips of somatic muscles, esophagus, and cuticle is proposed to move the lips.

The ultrastructure of the cuticle of the nematode Syphacia obvelata (Rudolphi, 1802). III. Cuticle associated with the male reproductive structures

1974 ◽  
Vol 52 (1) ◽  
pp. 179-182 ◽  
Author(s):  
T. A. Dick ◽  
K. A. Wright
Keyword(s):  
Body Wall ◽  
Matrix Material ◽  
Accessory Piece ◽  
The Body ◽  
The Other ◽  
Reproductive Structures ◽  
Material Forming ◽  
Syphacia Obvelata ◽  
Anal Papillae ◽  
Effective Transmission

Mamelons of male Syphacia obvelata are ventrally situated copulatory structures bounded by cuticle, and internally composed of muscles. Extracuticular spines are found at the apex of each annulus making up the mamelon. The cloaca is formed by an invagination of body wall cuticle, as is the spicule sheath (a portion of the cloacal wall surrounding the free end of the spicule). The spicule, accessory piece, and papillae are innervated and probably function as mechanoreceptors facilitating the positioning of the cloacal region over the vulva during copulation. Dense material forming the gubernaculum, spicule, and accessory piece is distinct from the body wall cuticle. The cortex and basal zones are apposed around the cloacal opening and probably strengthen this area. On the other hand, cuticle lining the cloaca is composed of cortex and an expanded inner zone of matrix material. This matrix material would allow considerable modification in the shape of the cloacal wall during copulation. The apposition of cortex and basal zones over the tip of anal papillae would ensure effective transmission of pressures to the nerve process.

On Microstrongylus genetiæ gen. and sp. nov., a Trichostrongyle Parasite of Genetta senegalensis

1927 ◽  
Vol 5 (2) ◽  
pp. 81-88 ◽  
Author(s):  
Thomas W. M. Cameron
Keyword(s):  
Small Intestine ◽  
Excretory Pore ◽  
Posterior Margin ◽  
Anterior Margin ◽  
Body Wall ◽  
Ventral Side ◽  
The Body ◽  
Zoological Society ◽  
Granular Inclusion ◽  
Cephalic Extremity

A Considerable number of specimens of this parasite were collected from the small intestine of a genette which died in the Gardens of the Zoological Society of London.The cuticle of the cephalic extremity is dilated anteriorly. This swelling is terminated posteriorly by the cuticle incurving to meet a raised ring on the body-wall, about the level of the junction of the anterior and second fifths of the œsophagus. There are no cervical papillæ present, and it is probable that this ring may be regarded as replacing them. Just anterior to the middle of the œsophageal region and at the level of the excretory pore is a cervical groove which completely encircles the body. Laterally the cuticle on the anterior margin is thickened; it is also thickened on the ventral side, but less so than laterally. These thickenings are reinforced by a granular inclusion in the cuticle. The posterior margin is thickened only in the region of the excretory pore.

The Organization of the Muscular System of Metridium senile

1951 ◽  
Vol s3-92 (17) ◽  
pp. 27-54
Author(s):  
E. J. BATHAM ◽  
C. F.A. PANTIN
Keyword(s):  
Body Wall ◽  
Functional Organization ◽  
Circular Muscle ◽  
Muscle Layer ◽  
The Body ◽  
Whole Body ◽  
Retractor Muscle ◽  
Muscle Fibres ◽  
Muscular System ◽  
Longitudinal Contraction

I. The muscular system of Metridium consists of fields of relatively short muscle-fibres. In extension these may exceed I mm. in length but are only about 0.5µ thick. They can shorten to about a fifth of the extended length. The fibres consist almost entirely of densely staining material. They form a connected network. At least in some cases the cells seem to be in contact rather than to form syncytial connexions. 2. Deformation of the body-wall is in part controlled by the contractility of the muscle-fibres and in part by the properties of the mesogloea. Longitudinal contraction of the body-wall is accompanied by great thickening of the substance of the mesogloea. That part of the mesogloea which carries the circular muscle-fibres of the body-wall does not thicken. It buckles, thereby throwing the muscular layer into folds. Buckling occurs during the shortening of almost every actinian tissue. The familiar folding seen in cross-sections of the retractors is a special case of excessive buckling which is permanent. 3. A natural limit to the extension of anemone tissue is reached when the muscle-layer is completely unbuckled. If contraction proceeds to a maximum, there is a second order of buckling by which the whole body-wall is thrown into folds. Con-traction ca n then proceed no further. 4. The function of the muscle-fields is analysed. The youngest cycles of mesenteries (‘imperfect microcnemes’) supply the longitudinal musculature of the column (parietal muscle). The older ‘imperfect retractor-bearers’ have only feeble parietal musculature, but possess a retractor muscle connecting the oral with the pedal disk. The perfect mesenteries have a similar organization to the imperfect retractor-bearers, and parti-cularly in the non-directive perfect mesenteries there is a well-developed sheet of radial (exocoelic) muscle whose reflex contraction opens the mouth. The vertical endocoelic muscle-fibres of all non-directive mesenteries fan out on to the pedal disk. On the exocoelic side, the parieto-basilarfans out from the pedal disk to the body-wall. As usual, the muscle-fields of the directives are developed on opposite sides from those of the non-directives. 5. The muscular plan of the pedal disk is compared with the tube foot of Asterias as described by J. E. Smith. There is a significant functional similarit y in the opera-tion of vertical, oblique, and radial muscles (basilars) bearing on the adhesive disk. The circular layer of the actinian foot has no analogue in the tube foot. It is primarily concerned with locomotion and not with adhesion. 6. The functional organization of the oral disk and tentacles is discussed. It differs from the rest of the body in the retention of ectodermal longitudinal muscle. This layer is responsible for the special movements executed in feeding. The significance of its physiological separation from the endodermal system is noted.

Locomotion and Coelomic Pressure in Lumbricus Terrestris L

1969 ◽  
Vol 51 (1) ◽  
pp. 47-58
Author(s):  
M. K. SEYMOUR
Keyword(s):  
Internal Pressure ◽  
Body Wall ◽  
Circular Muscle ◽  
Lumbricus Terrestris ◽  
The Body ◽  
Initial Penetration ◽  
Cine Film ◽  
Body Wall Muscles ◽  
Longitudinal Muscles ◽  
Do So

1. Crawling movement and burrowing of Lumbricus terrestris (L.) have been studied by continuous recording of internal pressure, direct observation and analysis of cine film. Frequency of locomotory waves is from 5 to 20 per min. Timing of protrusion of setae and of backward slip of points d'appui in locomotion have been observed and recorded. 2. In normal locomotion elongation of segments by contraction of the circular muscles gives rise to a discrete pressure pulse; shortening, by contraction of the longitudinal muscles, may or may not do so, depending on the position of the segment in the worm and the relative extent of contraction of the longitudinal and circular muscles. 3. Consideration of crawling and burrowing pressure records emphasizes the importance of (a) the circular muscles in extension of the head end in crawling and in initial penetration of the soil, and (b) the longitudinal muscles during burrowing, in dilating the burrow and drawing in more posterior segments 4. Mean pressures at circular and longitudinal muscle contraction are 12 and 7 cm. H2O respectively. The highest pressure recorded was 75 cm. H2O and accompanied violent squirming with evident contraction of all the body wall muscles. Resting pressures, shown in the absence of organized movement, are low (mean 0.26 cm. H2O). In both resting and crawling negative pressures sometimes occur and these are considered in relation to the inherent stiffness of the body wall and to the septate condition. 5. Tension in the longitudinal and circular muscle layers of a worm developing 75 cm. H2O internal pressure are calculated to be 265 and 1323 g./cm2. respectively, demonstrating in this example that, relative to the circulars, the longitudinal muscles are understressed by a factor of 5. Mean locomotory L.M. and C.M. peak values yield tension values of only 25 and 212 g./cm. respectively, and these are clearly well within the worm's capacity.

Lymphangiomatosis of the Body Wall: A Report of Two Cases Associated with Chylothorax and Fatal Outcome

1997 ◽  
Vol 17 (4) ◽  
pp. 617-624 ◽  
Author(s):  
Philippe Moerman ◽  
Chris Van Geet ◽  
Hugo Devlieger
Keyword(s):  
Body Wall ◽  
Fatal Outcome ◽  
The Body

scholarly journals A screen for genetic loci required for body-wall muscle development during embryogenesis in Caenorhabditis elegans.

Genetics ◽  
1994 ◽  
Vol 137 (2) ◽  
pp. 483-498
Author(s):  
J Ahnn ◽  
A Fire
Keyword(s):  
Caenorhabditis Elegans ◽  
Myosin Heavy Chain ◽  
Muscle Cell ◽  
Heavy Chain ◽  
Body Wall ◽  
Muscle Development ◽  
Contractile Function ◽  
The Body ◽  
Body Wall Muscle ◽  
Genetic Loci

Abstract We have used available chromosomal deficiencies to screen for genetic loci whose zygotic expression is required for formation of body-wall muscle cells during embryogenesis in Caenorhabditis elegans. To test for muscle cell differentiation we have assayed for both contractile function and the expression of muscle-specific structural proteins. Monoclonal antibodies directed against two myosin heavy chain isoforms, the products of the unc-54 and myo-3 genes, were used to detect body-wall muscle differentiation. We have screened 77 deficiencies, covering approximately 72% of the genome. Deficiency homozygotes in most cases stain with antibodies to the body-wall muscle myosins and in many cases muscle contractile function is observed. We have identified two regions showing distinct defects in myosin heavy chain gene expression. Embryos homozygous for deficiencies removing the left tip of chromosome V fail to accumulate the myo-3 and unc-54 products, but express antigens characteristic of hypodermal, pharyngeal and neural development. Embryos lacking a large region on chromosome III accumulate the unc-54 product but not the myo-3 product. We conclude that there exist only a small number of loci whose zygotic expression is uniquely required for adoption of a muscle cell fate.

scholarly journals Cloning and sequencing of cDNA of Sarcophaga peregrina humoral lectin induced on injury of the body wall.

1985 ◽  
Vol 260 (22) ◽  
pp. 12228-12233 ◽  
Author(s):  
H Takahashi ◽  
H Komano ◽  
N Kawaguchi ◽  
N Kitamura ◽  
S Nakanishi ◽  
...  
Keyword(s):  
Body Wall ◽  
The Body ◽  
Cloning And Sequencing

scholarly journals Mutations Affecting Nerve Attachment of Caenorhabditis elegans

Genetics ◽  
2001 ◽  
Vol 157 (4) ◽  
pp. 1611-1622 ◽  
Author(s):  
Go Shioi ◽  
Michinari Shoji ◽  
Masashi Nakamura ◽  
Takeshi Ishihara ◽  
Isao Katsura ◽  
...  
Keyword(s):  
Caenorhabditis Elegans ◽  
Nerve Cord ◽  
Ventral Nerve Cord ◽  
Body Wall ◽  
The Body ◽  
Genetic Loci ◽  
Muscle Attachment ◽  
C Elegans ◽  
Ventral Cord ◽  
Excretory Canal

Abstract Using a pan-neuronal GFP marker, a morphological screen was performed to detect Caenorhabditis elegans larval lethal mutants with severely disorganized major nerve cords. We recovered and characterized 21 mutants that displayed displacement or detachment of the ventral nerve cord from the body wall (Ven: ventral cord abnormal). Six mutations defined three novel genetic loci: ven-1, ven-2, and ven-3. Fifteen mutations proved to be alleles of previously identified muscle attachment/positioning genes, mup-4, mua-1, mua-5, and mua-6. All the mutants also displayed muscle attachment/positioning defects characteristic of mua/mup mutants. The pan-neuronal GFP marker also revealed that mutants of other mua/mup loci, such as mup-1, mup-2, and mua-2, exhibited the Ven defect. The hypodermis, the excretory canal, and the gonad were morphologically abnormal in some of the mutants. The pleiotropic nature of the defects indicates that ven and mua/mup genes are required generally for the maintenance of attachment of tissues to the body wall in C. elegans.

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