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.

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.

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.

Kinematic scaling of locomotion by hydrostatic animals: ontogeny of peristaltic crawling by the earthworm lumbricus terrestris

1999 ◽  
Vol 202 (6) ◽  
pp. 661-674 ◽  
Author(s):  
K.J. Quillin
Keyword(s):  
Body Mass ◽  
Body Wall ◽  
Deformable Body ◽  
Lumbricus Terrestris ◽  
The Body ◽  
Duty Factor ◽  
Body Segments ◽  
The Relationship ◽  
Dynamic Shape ◽  
Earthworm Lumbricus

This study examined the relationship between ontogenetic increase in body size and the kinematics of peristaltic locomotion by the earthworm Lumbricus terrestris, a soft-bodied organism supported by a hydrostatic skeleton. Whereas the motions of most vertebrates and arthropods are based primarily on the changes in the joint angles between rigid body segments, the motions of soft-bodied organisms with hydrostatic skeletons are based primarily on the changes in dimensions of the deformable body segments themselves. The overall kinematics of peristaltic crawling and the dynamic shape changes of individual earthworm segments were measured for individuals ranging in body mass (mb) by almost three orders of magnitude (0.012-8.5 g). Preferred crawling speed varied both within and among individuals: earthworms crawled faster primarily by taking longer strides, but also by taking more strides per unit time and by decreasing duty factor. On average, larger worms crawled at a greater absolute speed than smaller worms (U p2finity mb0.33) and did so by taking slightly longer strides (l p2finity mb0.41, where l is stride length) than expected by geometric similarity, using slightly lower stride frequencies (f p2finity mb-0.07) and the same duty factor (df p2finity mb-0.03). Circumferential and longitudinal body wall strains were generally independent of body mass, while strain rates changed little as a function of body mass. Given the extent of kinematic variation within and among earthworms, the crawling of earthworms of different sizes can be considered to show kinematic similarity when the kinematic variables are normalized by body length. Since the motions of peristaltic organisms are based primarily on changes in the dimensions of the deformable body wall, the scaling of the material properties of the body wall is probably an especially important determinant of the scaling of the kinematics of locomotion.

scholarly journals THE STRUCTURE OF THE SMOOTH MUSCLE FIBRES IN THE BODY WALL OF THE EARTHWORM

1957 ◽  
Vol 3 (1) ◽  
pp. 111-122 ◽  
Author(s):  
Jean Hanson
Keyword(s):  
Smooth Muscle ◽  
Phase Contrast ◽  
Body Wall ◽  
Longitudinal Muscle ◽  
Lumbricus Terrestris ◽  
Mirror Image ◽  
The Body ◽  
The Other ◽  
Muscle Fibres ◽  
Muscle Coat

1. The structure of the smooth muscle fibres in the longitudinal muscle coat of the body wall of Lumbricus terrestris has been investigated by phase contrast light microscopy and electron microscopy. 2. The muscle fibre is ribbon-shaped, and attached to each of its two surfaces is a set of myofibrils. These are also ribbon-shaped, and they lie with their surfaces perpendicular to the surfaces of the fibre, and their inner edges nearly meeting in the middle of the fibre. These fibrils are oriented at an angle to the fibre axis, and diminish greatly in width as they approach the edge of the fibre. The orientation of the set of fibrils belonging to one surface of the fibre is the mirror image of that of the set belonging to the other surface; thus, when both sets are in view in a fibre lying flat on one face, the fibre exhibits double oblique striation. A comparison of extended and contracted fibres indicates that as the fibre contracts, the angle made between fibre and fibril axes increases (e.g. from 5 to 30°) and so does the angle made between the two sets of fibrils (e.g. from 10 to 60°). 3. The myofibril, throughout its length, contains irregularly packed filaments, commonly 250 A in diameter, which are parallel to its long axis and remain straight in contracted muscles. Between them is material which probably consists of much finer filaments. Thus A and I bands are absent. 4. Bound to one face of each fibril, but not penetrating inside it, is a regularly spaced series of transverse stripes. They are of two kinds, alternating along the length of the fibril, and it is suggested that they are comparable to the Z and M lines of a cross-striated fibril. The spacing of these stripes is about 0.5 µ ("Z" to "Z") in extended muscles, and 0.25 µ in contracted muscles. A bridge extends from each stripe across to the stripeless surface of the next fibril.

scholarly journals Ontogenetic scaling of hydrostatic skeletons: geometric, static stress and dynamic stress scaling of the earthworm lumbricus terrestris

1998 ◽  
Vol 201 (12) ◽  
pp. 1871-1883 ◽  
Author(s):  
KJ Quillin
Keyword(s):  
Body Size ◽  
Body Wall ◽  
Dynamic Stress ◽  
Lumbricus Terrestris ◽  
Static Stress ◽  
The Body ◽  
Cross Sectional ◽  
Dynamic Stresses ◽  
Form And Function ◽  
And Function

Soft-bodied organisms with hydrostatic skeletons range enormously in body size, both during the growth of individuals and in the comparison of species. Therefore, body size is an important consideration in an examination of the mechanical function of hydrostatic skeletons. The scaling of hydrostatic skeletons cannot be inferred from existing studies of the lever-like skeletons of vertebrates and arthropods because the two skeleton types function by different mechanisms. Hydrostats are constructed of an extensible body wall in tension surrounding a fluid or deformable tissue under compression. It is the pressurized internal fluid (rather than the rigid levers of vertebrates and arthropods) that enables the maintenance of posture, antagonism of muscles and transfer of muscle forces to the environment. The objectives of the present study were (1) to define the geometric, static stress and dynamic stress similarity scaling hypotheses for hydrostatic skeletons on the basis of their generalized form and function, and (2) to apply these similarity hypotheses in a study of the ontogenetic scaling of earthworms, Lumbricus terrestris, to determine which parameters of skeletal function are conserved or changed as a function of body mass during growth (from 0.01 to 8 g). Morphometric measurements on anesthetized earthworms revealed that the earthworms grew isometrically; the external proportions and number of segments were constant as a function of body size. Calculations of static stresses (forces per cross-sectional area in the body wall) during rest and dynamic stresses during peristaltic crawling (calculated from measurements of internal pressure and body wall geometry) revealed that the earthworms also maintained static and dynamic stress similarity, despite a slight increase in body wall thickness in segment 50 (but not in segment 15). In summary, the hydrostatic skeletons of earthworms differ fundamentally from the rigid, lever-like skeletons of their terrestrial counterparts in their ability to grow isometrically while maintaining similarity in both static and dynamic stresses.

The Action of Drugs, Especially Acetylcholine, on the Annelid Body Wall (Lumbricus, Arenicola)

1939 ◽  
Vol 16 (3) ◽  
pp. 251-257
Author(s):  
K. S. WU
Keyword(s):  
Skeletal Muscle ◽  
Spontaneous Activity ◽  
Body Wall ◽  
Lumbricus Terrestris ◽  
The Body ◽  
Arenicola Marina ◽  
Earthworm Gut ◽  
Mammalian Intestine ◽  
Earthworm Lumbricus ◽  
Vertebrate Skeletal Muscle

1. The actions of certain drugs (acetylcholine, eserine, atropine, nicotine, adrenaline) on strips of the body wall of the earthworm (Lumbricus terrestris) and lugworm (Arenicola marina) are described. 2. The body wall of the earthworm and lugworm resembles the dorsum of the leech, and also vertebrate skeletal muscle, in the following points: relatively insensitive to acetylcholine alone, sensitivity to acetylcholine greatly increased by eserine, response to acetylcholine abolished by nicotine. In these points, the muscles mentioned contrast with the earthworm gut and the mammalian intestine, which are: very sensitive to acetylcholine alone, sensitivity not greatly increased by eserine, response to acetylcholine abolished by atropine. 3. The various types of body wall strip differ among themselves as regards spontaneous activity, response to eserine alone, and response to adrenaline.

Neuromuscular Junctions in the Body Wall Muscles of the Earthworm, Lumbricus Terrestris Linn

1970 ◽  
Vol 7 (1) ◽  
pp. 263-271
Author(s):  
P. J. MILL ◽  
M. F. KNAPP
Keyword(s):  
Synaptic Vesicles ◽  
Body Wall ◽  
Neuromuscular Junctions ◽  
Lumbricus Terrestris ◽  
The Body ◽  
Dense Material ◽  
Muscle Fibres ◽  
Membrane Material ◽  
Axonal Membrane ◽  
Body Wall Muscles

The fine structure of the neuromuscular Junctions in the body wall muscles of the earthworm is described. The segmental nerves send branches into the muscle layers. Axons in the nerve branches contain numerous synaptic vesicles and contact is established between these axons and muscle fibres or muscle tails; the latter may extend for a considerable distance from the muscle fibre. The cleft between the axolemma and sarcolemma is 85-120 nm wide and contains basement membrane material. At intervals small aggregations of electron-dense material are attached to the axonal membrane and synaptic vesicles are associated with these. The sarcolemma bears rather larger masses of dense material and is also specialized extracellularly.

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.

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