Memoirs: Studies on the Structure, Development, and Physiology of the Nephridia of Oligochaeta VI. The Physiology of Excretion and the Significance of the Enteronephric Type of Nephridial System in Indian Earthworms

1945 ◽  
Vol s2-85 (340) ◽  
pp. 343-389
Author(s):  
KARM NARAYAN BAHL
Keyword(s):  
Large Scale ◽  
Body Wall ◽  
Chloride Content ◽  
The Body ◽  
Regulatory Function ◽  
Coelomic Fluid ◽  
Brownish Yellow ◽  
Terrestrial Animal ◽  
First Time ◽  
Blood Pigment

1. In an earthworm, as in most aquatic invertebrates, urea and ammonia form the main bulk of nitrogenous excretion and there is no trace of uric acid. These excretory products are first formed in the body-wall and gut-wall, pass therefrom into the coelomic fluid and blood, and are thence eliminated to the exterior by the nephridia. In Pheretima urea and ammonia pass out from the nephridia to the exterior either directly through the skin or through the two ends of the gut. 2. Ammonia and urea have been estimated for the first time in the blood, coelomic fluid, and urine of the earthworm. It has been shown that blood is not a mere carrier of oxygen, as Rogers believed, but that it also takes part in carrying urea and ammonia from the body-wall and gut-wall to the nephridia. The blood of the earthworm does not coagulate, indicating absence of fibrinogen. 3. The role of the nephridia in excretion and osmotic regulation has been determined. A comparison of the osmotic pressures of blood, coelomic fluid, and urine shows that the coelomic fluid is hypotonic to the blood, and that urine is markedly hypotonic both to the blood and coelomic fluid. The protein and chloride contents of the blood, coelomic fluid, and urine have been determined with a view to elucidate the differences in their osmotic pressures. It has been found that the urine contains the merest trace of protein, but that the amount of proteins in the blood is about eight times that contained in the plasma of the coelomic fluid. On the contrary, the chloride content of the coelomic fluid-plasma is about 60 per cent, higher than that of the blood-plasma. 4. The part of urine which is excreted from the blood is probably a protein-free filtrate, but the nephridia reabsorb all the proteins passing into them with the coelomic fluid-plasma. Similarly, there is a reabsorption of chlorides on a large scale from the initial nephridial filtrate during its passage through the nephridia. 5. A convenient method has been devised for collecting urine of the earthworm, which has made it possible to collect as much as 25 c.c. of urine in two and a half hours. The rate of excretion of the urine has been determined and it has been found that in an earthworm living in water the outflow of urine in twenty-four hours must be more than 45 per cent, of its body-weight. 6. It seems that an earthworm, when submerged in water, can live like a fresh water animal, and its gut acts as an osmoregulatory organ in addition to the nephridia, but in the soil it lives like a terrestrial animal and the osmo-regulatory function is adequately discharged by the nephridia alone which reabsorb chlorides and proteins, and are also active in the conservation of water. In Pheretima and other earthworms with an enteronephric type of nephridial system, the gut takes a prominent part in reabsorbing the water of the nephridial fluid and conserving water to its maximum extent. 7. The phagocytic section (ciliated middle tube) believed by Schneider to be absent in the nephridia of Pheretima has been shown to be distinctly present; it is also present in the nephridia of Lampito , Eutyphoeus, and Tonoscolex. The brownish yellow granules characteristic of this phagocytic section form a heavy deposit in the septal nephridia of Pheretima posthuma, heavier than that described in Lumbricus. The deposit increases with the age of the earthworm and forms a ‘storage excretory product’. 8. Spectroscopic examination has revealed that these brownish yellow granules, so far believed to be of guanine, are really blood-pigment granules, since a pyridine solution of them shows the two characteristic bands of haemochromogen. With regard to the blood-pigment, the nephridia function as ‘storage kidneys’. 9. The mechanism of nephridial excretion of the earthworm can be analysed into processes of filtration, reabsorption, and chemical transformation. 10. It is probable that the dorsal and ventral phagocytic organs of earthworms are additional excretory organs.

The Ligamentary System and the Segmental Musculature of Nephtys

1960 ◽  
Vol s3-101 (54) ◽  
pp. 149-176
Author(s):  
R. B. CLARK ◽  
M. E. CLARK
Keyword(s):  
Body Wall ◽  
The Body ◽  
Power Stroke ◽  
Coelomic Fluid ◽  
Unusual Structure ◽  
Shock Absorbers ◽  
Proximal Half ◽  
Unique System ◽  
Body Wall Muscles ◽  
The Impact

Nephtys lacks circular body-wall muscles. The chief antagonists of the longitudinal muscles are the dorso-ventral muscles of the intersegmental body-wall. The worm is restrained from widening when either set of muscles contracts by the combined influence of the ligaments, some of the extrinsic parapodial muscles, and possibly, to a limited extent, by the septal muscles. Although the septa are incomplete, they can and do form a barrier to the transmission of coelomic fluid from one segment to the next under certain conditions, particularly during eversion of the proboscis. Swimming is by undulatory movements of the body but the distal part of the parapodia execute a power-stroke produced chiefly by the contraction of the acicular muscles. It is suspected that the extrinsic parapodial muscles, all of which are inserted in the proximal half of the parapodium, serve to anchor the parapodial wall at the insertion of the acicular muscles and help to provide a rigid point of insertion for them. Burrowing is a cyclical process involving the violent eversion of the proboscis which makes a cavity in the sand. The worm is prevented from slipping backwards by the grip the widest segments have on the sides of the burrow. The proboscis is retracted and the worm crawls forward into the cavity it has made. The cycle is then repeated. Nephtys possesses a unique system of elastic ligaments of unusual structure. The anatomy of the system is described. The function of the ligaments appears to be to restrain the body-wall and parapodia from unnecessary and disadvantageous dilatations during changes of body-shape, and to serve as shock-absorbers against the high, transient, fluid pressures in the coelom, which are thought to accompany the impact of the proboscis against the sand when the worm is burrowing. From what is known of its habits, Nephtys is likely to undertake more burrowing than most other polychaetes.

scholarly journals Reinterpretation of the enigmatic Ordovician genus Bolboporites (Echinodermata)

Zoosymposia ◽  
2019 ◽  
Vol 15 (1) ◽  
pp. 44-70
Author(s):  
EMERIC GILLET ◽  
BERTRAND LEFEBVRE ◽  
VERONIQUE GARDIEN ◽  
EMILIE STEIMETZ ◽  
CHRISTOPHE DURLET ◽  
...  
Keyword(s):  
Ct Scan ◽  
Body Wall ◽  
The Body ◽  
Precise Nature ◽  
Definitive Evidence ◽  
Wide Range ◽  
Ft Ir ◽  
First Time

Bolboporites is an enigmatic Ordovician cone-shaped fossil, the precise nature and systematic affinities of which have been controversial over almost two centuries. For the first time, a wide range of techniques (CT-scan, SEM, cathodoluminescence, XPL, UV epifluorescence, EBSD, FT-IR and XRF spectrometry) were applied to well-preserved specimens of Bolboporites from Norway and Russia. Our main finding confirms its echinoderm affinities, as shown by its stereomic microstructure and by the first definitive evidence of its monocrystalline nature. Each cone consists in a single, microporous calcitic crystal with a narrow longitudinal internal canal. These results are combined with all previous data on Bolboporites to critically discuss five alternative interpretations of this fossil, namely theca, basal cone, spine, columnal, and holdfast, respectively. The most parsimonious scenario considers Bolboporites as an isolated spine, which was articulated in life by a short biserial appendage to the body wall of an unknown echinoderm, possibly of echinozoan affinities.

Observations in the Skin Pigment and Amoebocytes, and the Occurrence of Phenolases in the Coelomic Fluid of Holothuria Forskali Delle Chiaje

1953 ◽  
Vol 31 (3) ◽  
pp. 529-539 ◽  
Author(s):  
Norman Millott
Keyword(s):  
Body Wall ◽  
Black Body ◽  
The Body ◽  
Coelomic Fluid ◽  
Histological Evidence ◽  
Oxidase System ◽  
Complete Investigation ◽  
Skin Pigment

The black body-wall pigment of Holothuria forskali shows the characteristics of melanin.From histological evidence it appears that the pigment is formed in association with the amoebocytes of the coelomic fluid, which eliminate the pigment in the body wall.The amoebocytes contain a phenolase system, distinct from the cytochromecytochrome oxidase system, with the properties of tyrosinase.The relation of these findings to those of a preceding and more complete investigation into melanogenesis in Diadema is discussed.

scholarly journals Memoirs: On a New Type of Nephridia found in Indian Earthworms of the Genus Pheretima

1919 ◽  
Vol s2-64 (253) ◽  
pp. 67-117
Author(s):  
KARM NARAYAN BAHL
Keyword(s):  
Blood Stream ◽  
The Body ◽  
Coelomic Fluid ◽  
Sphincter Muscle ◽  
Remarkable Feature ◽  
Dorsal Wall ◽  
New Type ◽  
Excretory Canals ◽  
First Time ◽  
Duct Opening

(1) There are three distinct kinds of nephridia in Pheretima posthnma and other species of the genus, namely, the septal, the pharyngeal and the integumentary, named according to the position they occupy in the worm; they differ from each other in size and also in respect of the place of opening of their ducts. (2) Each nephridium is a separate and discrete structure and there is no network of any kind, and therefore the terms "plectonephric" and "diffuse" are inapplicable to these nephridia, although the term "micronephridia" can be retained. (3) The integumentary nephridia are very minute and are hardly visible to the naked eye. Each of them has its own separate duct opening separately to the exterior on the skin. Each, segment has about 200 to 250 of them. The pharyngeal nephridia occur in paired tufts lying at the sides of the oesophagus in the fourth, fifth and sixth segments; these nephridial tufts have three pairs of ducts, one in each segment, which open into the buccal cavity and the pharynx in the second and fourth segments. (4) The septal nephridia are attached to both sides of the septa; they do not open on the skin, but are connected with an elaborate system of ducts which ultimately open into the lumen of the intestine mid-dorsally at segmental intervals. The system of ducts and openings is perfectly segmental in arrangement, and consists of a pair of septal excretory canals on each septum which open into a pair of supra-intestinal excretory ducts lying in the mid-dorsal line of the worm above the dorsal wall of the gut, these ducts communicating with the lumen of the intestine at each intersegmental place by means of a narrow ductule. This last feature is characteristic of this type of nephridial system, and the latter has therefore been termed the "enteronephric" type of nepliridial system. Bach septal nephridium has a remarkable feature in that it lies--the funnel and all--wholly within the bounds of a single segment. The septal canals, the supra-intestinal ducts and their openings into the lumen of the gut have been described here for the first time, and the segmental character of the nephridial system of Pheretima, which was denied by Beddard, has now been established. (5) The enteronephric nephridial system is probably a device for the conservation of water in this tropical genus, the gut-epithelium reabsorbing the water of the excretory fluid while letting the solid excretory matters pass out through the anus along with the fæces. (6) Each nephridium in Pheretima, like that in Lumbricus, is connected with two blood-vessels, one bringing blood to it and the other taking away the blood. The septal and the integumentary nephridia are supplied with blood from the ventral vessel through the parietal vessel and the septal branch, and the blood is returned from these nephridia to the general blood-stream via, the dorso-lateral vessel and the subneural vessel. The pharyngeal nephridia receive their blood-supply from the dorsal vessel, and the blood is returned from them to the lateral cesophageal vessels. (7) The intersegmental septa in Pheretima posthuma and other species have definite, circular or oval apertures, each with a sphincter muscle around it. It is suggested that by closing these apertures by means of sphincters there is a restriction of the cœlomic fluid to certain segments which become consequently turgid and stiff, and are thus able to help the setae in having a firm hold of the ground during the locomotory movements of the animal; this turgidity of the part of the body applying setse on to the ground seems necessary, since a limp part cannot fix its setæ on the substratum on which the worm moves.

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.

scholarly journals The rôle of the body fluid in relation to movement in soft-bodied invertebrates I. The burrowing of Arenicola

1947 ◽  
Vol 134 (877) ◽  
pp. 431-455 ◽  
Keyword(s):  
Body Fluid ◽  
Body Wall ◽  
The Body ◽  
Coelomic Fluid ◽  
Simple Condition ◽  
Muddy Sand ◽  
Fluid System ◽  
Quantitative Results ◽  
Pressure Changes

This investigation is an attempt to obtain quantitative results on the method of functioning of the body-wall muscle-coelomic fluid system of the lugworm which was chosen as an example of a worm having this system in a relatively simple condition. Measurements of the hydrostatic pressure developed in the coelomic fluid during various phases of activity, particularly during burrowing, were recorded, and the mechanism by which pressure is differentially distributed throughout the body is discussed. The relation of pressure changes to burrowing movements is described and some calculations of the thrust which can be exerted by the worms are given. It is shown that the forces available to the worms are insufficient to allow of straight­-forward burrowing and that the ability to burrow depends on the thixotropic properties of the muddy sand in which the animals live.

On chlorocruorin and haemoglobin

1949 ◽  
Vol 136 (884) ◽  
pp. 378-388 ◽  
Keyword(s):  
Carbon Monoxide ◽  
Oxygen Affinity ◽  
Coelomic Fluid ◽  
Functional Explanation ◽  
Respiratory Protein ◽  
First Time ◽  
Blood Pigment ◽  
In Cells

Chlorocruorin is a dichroic red-green respiratory protein. It is chemically similar to haemo­globin, and is only found dissolved in the blood of certain marine annelid worms. Chlorocruorin is the characteristic blood pigment of the Serpulimorpha (serpulids and sabellids), but in the genus Serpula both chlorocruorin and haemoglobin are present together in the blood. This is the first time that two respiratory pigments have been found in the blood of one animal. Young individuals have relatively more haemoglobin, older ones more chlorocruorin. Within the serpulid genus Spirorbis , one species has chlorocruorin in its blood, an other has haemoglobin, while a third has neither pigment. As their habitats are similar, no functional explanation for these differences suggests itself. The oxygen affinity of all chlorocruorins tested is considerably lower than that of most haemoglobins. But in Serpula the oxygen affinities of the chlorocruorin and haemoglobin are the same as one an other. The carbon monoxide affinity of chlorocruorin (in Branchiomma ) is higher than that of any haemoglobin. Although Serpulimorpha have chlorocruorin in their blood, the haem present in their tissues (muscles, eggs, sperm ) is protohaem, not chlorocruorohaem. One genus, Potamilla , with chlorocruorin in its blood, has haem oglobin in the muscles. Chlorocruorin is known only from blood, and from the mucous tube of Myxicola ; none has been found in cells. Coelomic fluid contains none. Protohaem is secreted in to the protective tubes of both serpulids and sabellids. A proto-haemochromogen is present in the gut fluid of serpulids, recalling that found in crustaceans and molluscs.

Studies on the Anatomy of Cimex lectularius L. II.

Parasitology ◽  
1924 ◽  
Vol 16 (3) ◽  
pp. 269-278 ◽  
Author(s):  
I. M. Puri
Keyword(s):  
Larval Stage ◽  
Body Wall ◽  
The Body ◽  
Cimex Lectularius ◽  
Epithelial Lining ◽  
Compound Structure ◽  
Larval Stages ◽  
First Time

The stink organs are different in structure and position in the adult and the larval stages.The stink organs of the adult are composed of (a) a pair of glands, (b) a central reservoir with two backwardly-directed lateral reservoirs, (c) a median kidney-shaped organ in the central reservoir, and (d) a pair of lateral external openings.Each gland is a multicellular compound structure, opening into the central reservoir. It is described for the first time in this paper.The whole of the stink organ of the adult is formed in the last larval stage from a pair of invaginations of the epithelial lining of the body-wall.In the larval stages the stink organs are simple glands, situated dorsally in abdominal segments III to V.The function of the stink organs is defensive and in the adult perhaps also sexual.

scholarly journals Diamonds are forever: the cortisone legacy

2007 ◽  
Vol 195 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Stephen G Hillier
Keyword(s):  
Rheumatoid Arthritis ◽  
Large Scale ◽  
Subsequent Development ◽  
The Body ◽  
Over The Counter ◽  
Associated Conditions ◽  
Health And Disease ◽  
Industrial Chemist ◽  
Wonder Drug ◽  
First Time

The year 1946 was not only the year that the Society for Endocrinology was founded, but also the year that Edward Kendall’s compound E (cortisone) was first synthesised by Louis Sarett. By 1948, sufficient quantities of compound E were available for the rheumatologist Philip Hench to test it successfully for the first time in a patient with rheumatoid arthritis. It was immediately hailed as a ‘wonder drug’ and was shown to be effective in a number of inflammation-associated conditions, most notably rheumatoid arthritis. The subsequent development of endocrinology as a discipline is inextricably linked to the chemistry, biology and medicine of antiinflammatory glucocorticoids. Sixty years after the first chemical synthesis of cortisone, corticosteroids remain among the top ten most commonly used prescription and over the counter drugs. Basic and clinical studies of glucocorticoid biosynthesis, metabolism and action have trail-blazed developments in endocrinology ever since. This article surveys the extraordinary cortisone timeline, from first synthesis until now. The concluding scientific message is that intracrine metabolism of cortisone to cortisol via 11βhydroxysteroid dehydrogenase type 1 likely sustains local amplification of glucocorticoid action at sites of inflammation throughout the body. The broader message is that the discovery of compound E by Kendall (basic scientist), its large-scale synthesis by Sarett (industrial chemist) and its therapeutic application by Hench (rheumatologist) serves as a paradigm for modern translational medicine. It is concluded that endocrinology will remain a force in health and disease if it continues to evolve sans frontières at the basic/applied/clinical science interface. A challenge for the Society for Endocrinology is to ensure this happens.

scholarly journals The morphology of autotomy structures in the sea cucumber Eupentacta quinquesemita before and during evisceration

2001 ◽  
Vol 204 (5) ◽  
pp. 849-863 ◽  
Author(s):  
M. Byrne
Keyword(s):  
Connective Tissue ◽  
Muscle Contraction ◽  
Sea Cucumber ◽  
Body Wall ◽  
The Body ◽  
Whole Body ◽  
Retractor Muscle ◽  
Coelomic Fluid ◽  
Ground Substance ◽  
Tissue Change

Evisceration in the dendrochirotid sea cucumber Eupentacta quinquesemita is a whole-body response involving a predictable series of events including muscle contraction and failure of three autotomy structures: (i) the introvert, the dexterous anterior extensible portion of the body wall, (ii) the tendon linking the pharyngeal retractor muscle to the longitudinal body wall muscle and (iii) the intestine-cloacal junction. The autotomy structures are histologically complex, consisting of muscle, nervous and connective tissue. Autotomy resulted from complete loss in the tensility of the connective tissue ground substance. Separation of the autotomy structures was facilitated by muscle contraction. The cell and tissue changes involved with autotomy were documented by microscopic examination of autotomising tissue. Change in the autotomy structures appears to initiate from the peritoneal side with delamination of the peritoneum followed by a wave of disruption as the connective tissue is infiltrated by coelomic fluid. Evisceration and autotomy in E. quinquesemita are neurally controlled, so particular attention was paid to the fate of neuronal elements. Neurosecretory-like processes containing large dense vesicles and axons were present in the connective tissue layers of the autotomy structures in association with extracellular matrix, muscles and neurons. These neuronal elements remained largely intact during autotomy and did not appear to be a source of factors that effect connective tissue change. They may, however, be involved in muscle activity. Holothuroid autotomy structures are completely or partially bathed in coelomic fluid, so there is potential for hormonal or neurosecretory activity using the coelomic fluid as a conduit. Connective tissue change during evisceration appears to be effected or mediated by an evisceration factor present in coelomic fluid that has a direct transmitter-like or neurosecretory-like mode of operation. The final outcome, expulsion of the viscera, is likely to result from a suite of factors that interact in a manner yet to be determined.

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