The Mechanism of Proboscis Movement in Arenicola

1954 ◽  
Vol s3-95 (30) ◽  
pp. 251-270
Author(s):  
G. P. WELLS
Keyword(s):  
Body Fluid ◽  
Body Wall ◽  
The Body ◽  
Stage I ◽  
Stage Iii ◽  
Forward Movement ◽  
Arenicola Marina ◽  
Buccal Mass ◽  
The Difference ◽  
Longitudinal Muscles

The mechanism of proboscis movement is analysed in detail in Arenicola marina L. and A. ecaudata Johnston, and discussed in relation to the properties of the hydrostatic skeleton. Proboscis activity is based on the following cycle of movements in both species. Stage I. The circular muscles of the body-wall and buccal mass contract; the head narrows and lengthens. Stage IIa. The circular muscles of the mouth and buccal mass relax; the gular membrane (or ‘first diaphragm’ of previous authors) contracts; the mouth opens and the buccal mass emerges. Stage IIb. The longitudinal muscles of the buccal mass and body-wall contract; the head shortens and widens and the pharynx emerges. Stage III. As Stage I. The two species differ anatomically and in their hydrostatic relationships. In ecaudata, the forward movement of body-fluid which extrudes and distends the proboscis is largely due to the contraction of the gular membrane and septal pouches. In marina, the essential mechanism is the relaxation of the oral region which allows the general coelomic pressure to extrude the proboscis. The gular membrane of marina contracts as that of ecaudata does, but its anatomy is different and it appears to be a degenerating structure as far as proboscis extrusion is concerned. Withdrawal of the proboscis may occur while the head is still shortening and widening in Stage IIb, or while it is lengthening and narrowing in Stage III. The proboscis is used both in feeding and in burrowing; in the latter case nothing enters through the mouth; the difference is largely caused by variation in the timing of withdrawal relative to the 3-stage cycle.

Studies on the Physiology of Ascaris Lumbricoides

1952 ◽  
Vol 29 (1) ◽  
pp. 1-21
Author(s):  
A. D. HOBSON ◽  
W. STEPHENSON ◽  
L. C. BEADLE
Keyword(s):  
Osmotic Pressure ◽  
Body Fluid ◽  
Body Wall ◽  
Sea Water ◽  
External Medium ◽  
Chloride Concentration ◽  
The Body ◽  
Intestinal Fluid ◽  
The Difference ◽  
Saline Medium

1. The total osmotic pressure, electrical conductivity and chloride concentration of the body fluid of Ascaris lumbricoides and of the intestinal contents of the pig have been measured. 2. The results obtained agree with the observations of previous workers that Ascaris normally lives in a hypertonic medium and that it swells or shrinks in saline media which are too dilute or too concentrated. 3. Experiments comparing the behaviour of normal and ligatured animals show that both the body wall and the wall of the alimentary canal are surfaces through which water can pass. 4. 30% sea water has been used as a balanced saline medium for keeping the worms alive in the laboratory. This concentration was selected as being the one in which there was least change in the body weight of the animals exposed to it. 5. The osmotic pressure of the body fluid of worms kept in 30% sea water is approximately the same as in animals taken directly from the pig's intestine. The body fluid of fresh worms is hypertonic to 30% sea water and hypotonic to the intestinal fluid. In 30% sea water the normal osmotic gradient across the body wall is therefore reversed. 6. In 30% sea water the total ionic concentration (as measured by the conductivity) decreases slightly, but the chloride concentration increases by about 50%, although still remaining much below that of the external medium. 7. Experiments in which the animals were allowed to come into equilibrium with various concentrations of sea water from 20 to 40% show that there are corresponding changes in the osmotic pressure of the body fluid which is, however, always slightly above that of the saline medium. The conductivity also changes in a similar manner but is always less than that of the medium, and the difference between the two becomes progressively greater the more concentrated the medium. 8. The chloride concentration of the body fluid varies with but is always below that of the external medium, whether this is intestinal fluid or one of the saline media. In the latter the difference between the internal and external chloride concentrations is least in 20% sea water and becomes progressively greater as the concentration of the medium is increased. 9. Experiments with ligatured worms and with eviscerated cylinders of the body wall show that these share the capacity of the normal worm to maintain the chloride concentration of the body fluid below that of the environment. This power is not possessed by cylinders composed of the cuticle alone. 10. If the worms which have had their internal chloride concentration raised by exposure to 30% sea water are transferred to a medium composed of equal volumes of 30% sea water and isotonic sodium nitrate solution, the chloride concentration of the body fluid is reduced to a value below that of the external medium. This phenomenon is also displayed by worms ligatured after removal from the 30% sea water and, to an even more marked degree, by eviscerated cylinders of the body wall. 11. It is concluded that Ascaris is able to maintain the chloride concentration of the body fluid below that of the external medium by an process of chloride excretion against a concentration gradient, and that this mechanism is resident in the body wall, the cuticle being freely permeable to chloride.

Observations on the Burrowing of Arenicola Marina (L.)

1966 ◽  
Vol 44 (1) ◽  
pp. 93-118
Author(s):  
E. R. TRUEMAN
Keyword(s):  
High Pressure ◽  
Hydrostatic Pressure ◽  
Body Wall ◽  
Circular Muscle ◽  
The Body ◽  
Power Stroke ◽  
Arenicola Marina ◽  
Resting Pressure ◽  
Longitudinal Muscles ◽  
Trunk Segments

1. Continuous recordings of the hydrostatic pressure in the coelom of Arenicola marina show a resting pressure of about 2 cm. of water in a non-burrowing worm. During burrowing a series of pressure peaks is produced and these gradually increase in amplitude up to 110 cm. as burrowing progresses. 2. The pressure peaks are of 2 sec. duration, occur at intervals of 5-7 sec., and for each there is a major contraction of the circular muscles followed by the shortening of the longitudinal muscles. The main power stroke in producing the high pressure is the contraction of the longitudinal muscles of most of the trunk segments. The sequence of muscular contractions and the phases of burrowing are considered. 3. The pressure is utilized at the anterior end of the worm both to aid passage through the sand and to anchor the head while the posterior segments are pulled into the burrow. 4. At maximum pressures the tension developed in the circular muscle of the body wall is estimated to be 3 kg./cm.2, while the resting pressure corresponds to less than 7% of this.

Memoirs: On the Reproductive Processes of the Earthworm, Lumbricus Terrestris

1925 ◽  
Vol s2-69 (274) ◽  
pp. 245-290
Author(s):  
A. J. GROVE
Keyword(s):  
Body Wall ◽  
Seminal Fluid ◽  
Lumbricus Terrestris ◽  
The Body ◽  
The Other ◽  
Reproductive Processes ◽  
Longitudinal Muscles ◽  
Earthworm Lumbricus

During the sexual congress of L.terrestris, the co-operating worms become attached to one another in a head-to-tail position in such a way that segments 9-11 of one are opposed to the clitellum of the other, and vice versa. At these points the attachment between the worms is an intimate one, assisted by the secretion of the glands associated with the diverticula of the setal pores found in certain segments, and is reinforced by the mutual penetration of the setae into the opposed body-surfaces. There is also a slighter attachment between segment 26 of one and 15 of the other. Each worm is enclosed in a slime-tube composed of mucus secreted from the epidermis. The exchange of seminal fluid is a mutual one. The fluid issues from the apertures of the vasa deferentia in segment 15, and is conducted beneath the slime-tube in pit-like depressions in the seminal grooves, which extend from segment 15 to the clitellum on each side of the body, to the clitellum, where it accumulates in the space between the lateral surfaces of segments 9-11 of one worm and the clitellum of the other. Eventually it becomes aggregated into masses in the groove between segments 9 and 10, and 10 and 11, and passes thence into the spermathecae. The seminal groove and its pit-like depressions are brought into existence by special muscles lying in the lateral blocks of longitudinal muscles of the body-wall.

The locomotion of the acanthor of Moniliformis dubius (Archiacanthocephala)

Parasitology ◽  
1971 ◽  
Vol 62 (1) ◽  
pp. 35-47 ◽  
Author(s):  
P. J. Whitfield
Keyword(s):  
Intermediate Host ◽  
Body Wall ◽  
The Body ◽  
Research Fellowship ◽  
Wall Movement ◽  
Hydrostatic Skeleton ◽  
Laboratory Facilities ◽  
Longitudinal Muscles ◽  
Shape Changes

The mature egg and the acanthor of Moniliformis dubius have been redescribed with special emphasis on the features relevant to the locomotion of this larval acanthocephalan. The movements of acanthors have been analysed by the use of frame by frame study of filmed records of motile acanthors. Acanthors appear to use the same mode of locomotion for hatching, locomotion within the gut of the intermediate host and penetration of the host's gut wall. Movement is produced by a set of spiralled, longitudinal muscles in the body wall of the hind body and two rostellar retractor muscles. This musculature acts both directly on the body wall and indirectly by hydraulic effects via the hydrostatic skeleton of pseudocoelomic fluid. The spiny evertable rostellum and the backward facing spines of the hind body are the means whereby shape changes of the acanthor interact with the immediate environment to produce effective progression.I should like to thank Professor D. Arthur for the provision of laboratory facilities, Dr D. W. T. Crompton for the initial gift of eggs of M. dubius and Mr R. D. Reed for invaluable assistance with microcinematographic technique. The work was carried out during the tenure of a Nuffield Foundation Research Fellowship.

Paramyosin isoforms of Schistosoma mansoni are phosphorylated and localized in a large variety of muscle types

Parasitology ◽  
1996 ◽  
Vol 112 (5) ◽  
pp. 459-467 ◽  
Author(s):  
J. Schmidt ◽  
O. Bodor ◽  
L. Gohr ◽  
W. Kunz
Keyword(s):  
Schistosoma Mansoni ◽  
Specific Antibody ◽  
Body Wall ◽  
Uranyl Acetate ◽  
The Body ◽  
Striated Muscles ◽  
Western Blots ◽  
Muscle Types ◽  
Longitudinal Muscles

SUMMARYParamyosin, although a widely distributed muscle component among invertebrates, has hitherto not clearly been shown to occur in the muscles of schistosomes. Instead, it has been reported to occur in the tegument. In the present study, a specific antibody reacting with each of 10 isoforms of paramyosin was used for light microscopical immunolocalization in sections of Schistosoma mansoni. Specimens were fixed by a new method to immobilize antigens with uranyl acetate–trehalose–methanol. In cercariae, schistosomula, and adults, the circular and longitudinal muscles of the body wall, the dorsoventral muscles and those surrounding the gut and the pharynx as well as the fast moving cross-striated muscles of the tail of cercariae intensely reacted with the antibody. However, neither immunohistologically nor on Western blots of isolated tegument, were indications found for the presence of paramyosin in the tegument. In vivo phosphorylation and binding of anti-phospho-tyrosine and anti-phospho-serine antibodies show phosphorylation of paramyosin which probably is responsible for the generation of the isoforms.

Serological responses to Ascaris suum adult worm antigens in Iberian finisher pigs

2003 ◽  
Vol 77 (2) ◽  
pp. 167-172 ◽  
Author(s):  
E. Frontera ◽  
F. Serrano ◽  
D. Reina ◽  
M. Alcaide ◽  
J. Sánchez-López ◽  
...  
Keyword(s):  
Adult Worm ◽  
Body Fluid ◽  
Body Wall ◽  
Ascaris Suum ◽  
The Body ◽  
Enzyme Linked Immunosorbent Assay ◽  
Molecular Weights ◽  
Young Pigs ◽  
Density Values ◽  
Intestinal Worm

AbstractAdult Ascaris suum were dissected to obtain different worm components (body wall, body fluid, ovaries, uterus and oesophagus) which were used as antigens when testing 95 sera of naturally A. suum-infected Iberian pigs by enzyme-linked immunosorbent assay (ELISA) and Western blot (WB). Pigs with patent Ascaris infections had significantly lower ELISA optical density values than pigs without adult worms when using the body fluid and the body wall as antigens. A poor negative correlation was found between adult intestinal worm burden or eggs in faeces and specific antibody responses, measured by ELISA and WB using all antigens. By WB, the recognition of specific bands was variable, but three groups of bands with molecular weights of 97 kDa, 54–58 kDa and 42–44 kDa were generally recognized by sera from naturally infected pigs as well as from hyperimmunized pigs when using the five antigen extracts. The ELISA and WB techniques may be used for immunodiagnosis, using somatic adult worm antigens, to declare young pigs to be Ascaris-free but cannot be used for individual Ascaris-diagnosis in adult Iberian pigs.

scholarly journals The Arginase Activity of the Tissues of the Earthworms Lumbricus Terrestris L., and Eisenia Foetida (Savigny)

1960 ◽  
Vol 37 (4) ◽  
pp. 775-782
Author(s):  
A. E. NEEDHAM
Keyword(s):  
Body Wall ◽  
Lumbricus Terrestris ◽  
Total Activity ◽  
The Body ◽  
Arginase Activity ◽  
Unit Weight ◽  
Eisenia Foetida ◽  
Previous Evidence ◽  
Urea Production ◽  
The Difference

1. The difference in arginase activity between the tissues of Eisenia and those of Lumbricus shows a relationship to the difference in urea output by living worms of the two species under the same dietary régime. 2. In Eisenia the difference in activity between the tissues of fasting and feeding worms is much smaller than in Lumbricus. The specific outputs of urea by living, fasting and feeding worms likewise differ less than in Lumbricus. 3. These facts strengthen previous evidence in favour of a Krebs-Henseleit type of mechanism for urea production in earthworms. 4. In Eisenia the difference in arginase activity between gut and body wall is similar to, but smaller than, that in Lumbricus, and the body wall makes a major contribution to the total activity. 5. The combined concentrations of ammonia-, amino-, and urea-nitrogen initially present in homogenates of the tissues of these worms are proportional to the combined amounts of the three components excreted per unit weight by living worms of the same species and régime. 6. The two species differ in a number of other properties investigated.

scholarly journals The Movements of the Proboscis in Glycera Dibranchiata Ehlers

1937 ◽  
Vol 14 (3) ◽  
pp. 290-301
Author(s):  
G. P. WELLS
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Body Wall ◽  
The Body ◽  
Inhibitory Influence ◽  
Spontaneous Movement ◽  
Arenicola Marina ◽  
Glycera Dibranchiata ◽  
The Central Nervous System ◽  
Nervous Conduction

1. The gut of Glycera consists of (a) the buccal tube, (b) the pharynx, containing the jaws with their associated muscles and glands and the principal stomatogastric ganglia, (c) the oesophagus, leading from the pharynx to (d) the intestine, in which digestion occurs. 2. An "isolated extrovert" preparation is described, consisting of the buccal tube, pharynx and oesophagus. The movements of the buccal tube and oesophagus are recorded separately. The preparation has the following properties: (a) The buccal tube shows vigorous, rapid contractions with a somewhat irregular rhythm. These contractions are due to impulses coming forwards from the pharynx, the buccal tube itself having little power of spontaneous movement. (b) The oesophagus shows tone-waves, on which more rapid contractions of small amplitude may be superposed. These contractions and tone-waves are due to impulses originating in the wall of the oesophagus itself. (c) In a few preparations only, synchronous movements of buccal tube and oesophagus were seen. The site of origin of this synchronous activity was not determined. 3. An "extrovert-body wall" preparation is described, in which the movements of the body wall and buccal tube are separately recorded while the normal nervous conduction paths between them remain intact. The preparation has the following properties: (a) In most cases the body wall shows slight movements only, and the buccal tube moves little or not at all. If, however, the buccal tube be cut across close to the mouth, it begins an irregular rhythm of vigorous contractions, due to impulses originating in the pharynx, which usually continues without diminution for hours. The quiescence of the buccal tube before this cut is made indicates that the central nervous system normally exerts an inhibitory influence on the pharynx. (b) In a few preparations, correlated outbursts of contraction in the body wall and buccal tube were seen. These outbursts, which possibly correspond to extrusion movements of the intact worm, are due to impulses originating in the central nervous system. 4. The results are compared with those previously obtained on Arenicola marina, and reported in an earlier paper.

Excretion of thiosulphate, the main detoxification product of sulphide, by the lugworm arenicola marina L

1999 ◽  
Vol 202 (7) ◽  
pp. 855-866 ◽  
Author(s):  
K. Hauschild ◽  
W.M. Weber ◽  
W. Clauss ◽  
M.K. Grieshaber
Keyword(s):  
Body Wall ◽  
Sea Water ◽  
The Body ◽  
Cell Junctions ◽  
Metabolic Inhibitors ◽  
Coelomic Fluid ◽  
Arenicola Marina ◽  
Double Exponential ◽  
Electrophysiological Measurements ◽  
Double Exponential Function

Thiosulphate, the main sulphide detoxification product, is accumulated in the body fluids of the lugworm Arenicola marina. The aim of this study was to elucidate the fate of thiosulphate. Electrophysiological measurements revealed that the transepithelial resistance of body wall sections was 76+/−34 capomega cm2 (mean +/− s.d., N=14), indicating that the body wall of the lugworm is a leaky tissue in which mainly paracellular transport along cell junctions takes place. The body wall was equally permeable from both sides to thiosulphate, the permeability coefficient of which was 1. 31×10(−)3+/−0.37×10(−)3 cm h-1 (mean +/− s.d., N=30). No evidence was found for a significant contribution of the gills or the nephridia to thiosulphate permeation. Thiosulphate flux followed the concentration gradient, showing a linear correlation (r=0.997) between permeated and supplied (10–100 mmol l-1) thiosulphate. The permeability of thiosulphate was not sensitive to the presence of various metabolic inhibitors, implicating a permeation process independent of membrane proteins and showing that the lugworm does not need to use energy to dispose of the sulphide detoxification product. The present data suggest a passive permeation of thiosulphate across the body wall of A. marina. In live lugworms, thiosulphate levels in the coelomic fluid and body wall tissue decreased slowly and at similar rates during recovery from sulphide exposure. The decline in thiosulphate levels followed a decreasing double-exponential function. Thiosulphate was not further oxidized to sulphite or sulphate but was excreted into the sea water.

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