The Mechanism of Marine Osmoregulation in the Lampern (Lampetra Fluviatilis L.) and the Causes of its Breakdown During the Spawning Migration

1958 ◽  
Vol 35 (3) ◽  
pp. 649-665
Author(s):  
R. MORRIS
Keyword(s):  
Urine Output ◽  
Sea Water ◽  
Freezing Point ◽  
Spawning Migration ◽  
Lampetra Fluviatilis ◽  
Monovalent Ions

1. Some fresh-run lamperns can osmoregulate in 50% sea water (Δ = 0.970° C), where they can maintain plasma freezing-point depressions of about 057° C. 2. An analysis of the mechanism of osmoregulation in these animals shows that it is similar in many respects to that employed by marine teleosts. The lampern swallows sea water and absorbs a solution containing a high proportion of monovalent ions into its blood. It has been calculated that chloride is excreted by an extra-renal route, presumably by means of chloride excretory cells which have been discovered in the gills. The rate of extra-renal loss of water is high and the urine output is negligible. 3. Many fresh-run animals are unable to osmoregulate. In some cases the capacity to swallow sea water becomes reduced, whilst in others the number of chloride excretory cells is diminished--an indication that the extra-renal excretory mechanism is failing. Both of these mechanisms regress simultaneously in some animals.

Lack of glomerular intermittency in the river lamprey lampetra fluviatilis acclimated to sea water and following acute transfer to iso-osmotic brackish water

1999 ◽  
Vol 202 (8) ◽  
pp. 939-946 ◽  
Author(s):  
J.A. Brown ◽  
J.C. Rankin
Keyword(s):  
Fresh Water ◽  
Brackish Water ◽  
Urine Output ◽  
Neural Control ◽  
Sea Water ◽  
Osmotic Gradient ◽  
Vascular Perfusion ◽  
Lampetra Fluviatilis ◽  
River Lamprey ◽  
Firm Evidence

Previous studies have suggested that in the lamprey Lampetra fluviatilis, in contrast to teleost fish, all glomeruli are actively filtering. In the present study, we have applied the ferrocyanide technique to obtain more definitive values for the population of filtering nephrons in the lamprey under conditions of high (in fresh water) and low (in sea water) glomerular filtration rate (GFR) and when the branchial osmotic gradient was eliminated by acute transfer of freshwater lampreys to iso-osmotic brackish water. These studies demonstrated that the renal antidiuresis in lampreys acclimated to full-strength sea water does not involve any reduction in the filtering population of glomeruli. Transfer to brackish water significantly reduced GFR and thereby urine flow rate (287+/−23 ml kg-1 24 h-1 in fresh water; 6.9+/−2.5 ml kg-1 24 h-1 in brackish water). In four of the eight fish examined, 100 % of glomeruli remained filtering; in the other four fish, non-filtering glomeruli occurred in patches along the kidney, always associated with an absence of vascular perfusion, which implies possible endocrine/neural control of vascular tone. The numbers of non-filtering glomeruli were always small, and these glomeruli do not appear to make a major contribution to the overall decline in urine output. The results provide firm evidence that although lampreys, like teleosts, show considerable variations in urine output, the renal mechanisms by which lampreys and the teleosts achieve this differ fundamentally, with glomerular intermittency playing little or no part in the lamprey.

Studies on Salt and Water Balance in Myxine Glutinosa (L.)

1965 ◽  
Vol 42 (2) ◽  
pp. 359-371
Author(s):  
R. MORRIS
Keyword(s):  
Water Balance ◽  
Sea Water ◽  
External Medium ◽  
Freezing Point ◽  
Freezing Point Depression ◽  
High Concentration ◽  
After Effects ◽  
Monovalent Ions ◽  
Calcium Magnesium ◽  
Salt And Water Balance

1. Measurements of freezing-point depression and chemical analysis have been made of the plasma and urine of Myxine. 2. The plasma is generally slightly hypertonic to sea water whilst the urine tends to be slightly hypotonic to the blood. 3. The urinary output is low (5·4±1·6 ml./kg./day) and the majority of animals do not swallow sea water. 4. Analyses of plasma and urine indicate that the kidney participates in ionic regulation by reducing the concentrations of calcium, magnesium and sulphate in the plasma relative to sea water. Chloride seems to be conserved whilst potassium may be conserved or excreted. The high concentration of magnesium in the plasma of animals kept in static sea water may be caused by the after effects of urethane. These animals continue to excrete magnesium at normal rates. 5. The rates at which calcium, magnesium and sulphate enter an animal which does not swallow sea water are proportional to the diffusion gradients which exist between the external medium and the plasma. The situation is more complicated for monovalent ions, but there is no evidence of specialized ion-transporting cells within the gill epithelium. 6. In those animals which swallow sea water the amounts of ions absorbed from the gut are very large compared with the renal output and it would therefore seem unlikely that swallowing is part of the normal mechanism of salt and water balance. 7. It is argued that the mechanism of salt and water balance in Myxine is likely to be primitive and that the vertebrate glomerulus was probably developed originally in sea water as an ion-regulating device.

Localization of Ion-Transport in the Intestine Of The Migrating River Lamprey, Lampetra Fluviatilis L

1973 ◽  
Vol 58 (1) ◽  
pp. 165-176
Author(s):  
ALAN D. PICKERING ◽  
R. MORRIS
Keyword(s):  
Ion Transport ◽  
Sea Water ◽  
Water Flux ◽  
Ion Flux ◽  
Lampetra Fluviatilis ◽  
River Lamprey ◽  
Monovalent Ions ◽  
Anterior Intestine ◽  
Monovalent Ion ◽  
Columnar Cells

1. Isolated intestinal preparations from migrating Lampetra fluviatilis re-adapted to 50% sea water were used to localize ion transport. 2. A large, active, monovalent-ion flux was found in the anterior intestine and its magnitude decreased towards the posterior end of the intestine. 3. The monovalent-ion flux is responsible for a net water flux from mucosa to serosa in the anterior intestine. 4. It is tentatively suggested that both sodium and chloride are actively transported by the mucosa. The divalent ions may be carried along with the monovalent ions to a limited extent. 5. Studies at the light- and electron-microscope levels indicate that columnar cells of the anterior intestine are responsible for ion transport, and there is evidence that the same cells produce mucus.

Some Aspects of the Structure and Cytology of the Gills of Lampetra fluviatilis

1957 ◽  
Vol s3-98 (44) ◽  
pp. 473-485
Author(s):  
R. MORRIS
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Gill Filament ◽  
Spawning Migration ◽  
Transitional Epithelium ◽  
Basal Cells ◽  
Mucous Cells ◽  
Gill Epithelium ◽  
Basal Nuclei ◽  
Monovalent Ions

A description is given of the structure and vascularization of the lampern gill. A comparison of the cellular components of the gill epithelium taken from lamperns at various stages of their spawning migration show that certain types of cells are common to all animals. These include the cells covering the gill platelets, the mucous cells, and certain basal cells from which others originate. The mucous cells are quite different in structure from those of teleosts. There is a progressive loss of large acidophilic cells from certain regions of the gill filament as animals enter fresh water during the earlier stages of the spawning migration. These cells are similar in both structure and location to those described as chloride excretory cells from the gills of marine teleosts. They are typically large, flask-shaped cells with basal nuclei and they are filled with rod-shaped or spherical mitochondria. It is believed that they are responsible for the extra-renal excretion of monovalent ions during the process of marine osmoregulation in the lampern. The chloride excretory cells are very numerous in a limited number of fresh-run animals which are able to osmoregulate in 50% sea water. In the normal course of events the chloride excretory cells are replaced by a smaller type of cell which is also rich in mitochondria, but unlike the excretory cells these lie at the surface of a transitional epithelium. It is argued that these cells may be responsible for ion uptake from fresh water in the maturing animal. In male lamperns, large glandular cells of unknown function appear in the gill epithelium as the animal nears the time of spawning.

The Effects of Salinity on Herring After Metamorphosis

1961 ◽  
Vol 41 (1) ◽  
pp. 37-48 ◽  
Author(s):  
F. G. T. Holliday ◽  
J. H. S. Blaxter
Keyword(s):  
Salinity Tolerance ◽  
Blood Concentration ◽  
Sea Water ◽  
Freezing Point ◽  
Tolerance Range ◽  
Blood Concentrations

The salinity tolerance of herring 9-ca 24 cm in length was found to lie between 6‰0 and 40–45‰0.Determinations of changes in weight and blood concentration (by measurement of the freezing-point), when herring were transferred from one salinity to another, demonstrated that extensive changes occurred in the blood. Under these conditions the herring experienced and survived blood concentrations equivalent to salinites of 13–22·5‰. A recovery to near normal (δ0·95 ≡ 15·8‰) took place in all the salinities within the tolerance range.Badly descaled herring in sea water showed large increases in blood concentration before death.A study of the kidney of the herring indicated that the ability to withstand the low salinities for long periods probably rested in the high glomerular count of the kidney.The importance of damage to the skin for survival is discussed in relation to tagging experiments.The results are also discussed in relation to the evolution of the herring.

The ice nucleating ability of macromolecules in immersion freezing decreases in the presence of salts: Implications for freezing point depression calculations

2021 ◽  
Author(s):  
Jon F. Went ◽  
Jeanette D. Wheeler ◽  
François J. Peaudecerf ◽  
Nadine Borduas-Dedekind
Keyword(s):  
Sea Water ◽  
Freezing Point ◽  
Pure Water ◽  
Salt Content ◽  
Mixed Phase ◽  
Cloud Formation ◽  
Sea Spray ◽  
Freezing Point Depression ◽  
Immersion Freezing ◽  
Mixed Phase Clouds

<p>Cloud formation represents a large uncertainty in current climate predictions. In particular, ice in mixed-phase clouds requires the presence of ice nucleating particles (INPs) or ice nucleating macromolecules (INMs). An influential population of INPs has been proposed to be organic sea spray aerosols in otherwise pristine ocean air. However, the interactions between INMs present in sea water and their freezing behavior under atmospheric immersion freezing conditions warrants further research to constrain the role of sea spray aerosols on cloud formation. Indeed, salt is known to lower the freezing temperature of water, through a process called freezing point depression (FPD). Yet, current FPD corrections are solely based on the salt content and assume that the INMs’ ice nucleation abilities are identical with and without salt. Thus, we measured the effect of salt content on the ice nucleating ability of INMs, known to be associated with marine phytoplankton, in immersion freezing experiments in the Freezing Ice Nuclei Counter (FINC) (Miller et al., AMTD, 2020). We measured eight INMs, namely taurine, isethionate, xylose, mannitol, dextran, laminarin, and xanthan as INMs in pure water at temperatures relevant for mixed-phase clouds (e.g. 50% activated fraction at temperatures above –23 °C at 10 mM concentration). Subsequently, INMs were analyzed in artificial sea water containing 36 g salt L<sup>-1</sup>. Most INMs, except laminarin and xanthan, showed a loss of ice activity in artificial sea water compared to pure water, even after FPD correction. Based on our results, we hypothesize sea salt has an inhibitory effect on the ice activity of INMs. This effect influences our understanding of how INMs nucleate ice as well as challenges our use of FPD correction and subsequent extrapolation to ice activity under mixed-phase cloud conditions.</p>

Characteristics of Sea-Water Ice Slurry for Cooling of Fish

2013 ◽  
Vol 388 ◽  
pp. 123-127 ◽  
Author(s):  
Agus Sunjarianto Pamitran ◽  
Helmi Dadang Ardiansyah ◽  
Mach Novviali
Keyword(s):  
Solid Surface ◽  
Chemical Equilibrium ◽  
Sea Water ◽  
Freezing Point ◽  
Good Time ◽  
Ice Slurry ◽  
High Quality ◽  
Experimental Conditions ◽  
Water Ice ◽  
Cooling Method

A more effective of cooling method is necessary for fish storage to get high quality and long freshness of fish. Ice block is not sufficient for fish storage because of its hard-solid surface that can damage the fish. Moreover for some remote area it is difficult to find ice block in good time with reasonable/low price. One solution for this problem is the using of sea-water ice slurry for fish cooling. Ice slurry is formed when the sea-water temperature goes down to its freezing point, when the early nucleation is formed. Crystal ice can be formed when chemical equilibrium is occurred. The purpose of this present study is to observe the characteristics of ice slurry generation using scraper blade evaporator and orbital rod evaporator. The experiment is done under some experimental conditions.

scholarly journals Ice-Ocean Interaction On Ronne Ice Shelf, Antarctica

1990 ◽  
Vol 14 ◽  
pp. 341
Author(s):  
A. Jenkins ◽  
C.S.M. Doake
Keyword(s):  
Cold Water ◽  
Sea Water ◽  
Freezing Point ◽  
Accumulation Rate ◽  
Weddell Sea ◽  
Shear Stresses ◽  
Strain Rates ◽  
Horizontal Shear ◽  
Ice Shelf ◽  
Ice Stream

A detailed glaciological study of Ronne Ice Shelf has been undertaken along a flowline extending from Rutford Ice Stream grounding line to the ice front. Measurements of velocity, surface elevation, ice thickness, surface temperature and accumulation rate have been made at a total of 28 sites; at 17 of these ice deformation rates are also known. Although no direct measurements of basal conditions have been made, these can be deduced from observations made at the surface. Assuming the ice shelf to be in a steady state, the basal mass balance can be calculated at points where strain-rates are known. Information on the spatial distribution of basal saline ice layers can also be obtained from radio-echo sounding data. The derived pattern of basal melting and freezing influences both the ice shelf and the underlying ocean. Vertical heat advection modifies the temperature distribution within the ice shelf, which determines its dynamic response to driving and restraining forces through the temperature-dependent ice-flow law. Using measured strain-rates and calculated temperature profiles, the restraint generated by horizontal shear stresses can be derived for points on the flowline. It is the cumulative effect of these forces which controls the discharge of grounded ice from Rutford Ice Stream. Cooling of sea-water to its pressure melting point by melting of ice at depth has two important results. The outflow of cold, dense Ice Shelf Water, produced by this mechanism, is a major source of Antarctic Bottom Water, formed as it mixes at depth with the warmer waters of the Weddell Sea (Foldvik and Gammelsrod, 1988). If the cold water is forced up to shallower depths, frazil ice will be produced as the pressure freezing point rises, resulting in basal accretion if this occurs beneath the ice shelf.

scholarly journals Thermal Regime of George VI Ice Shelf, Antarctic Peninsula (Abstract)

1988 ◽  
Vol 11 ◽  
pp. 206 ◽  
Author(s):  
J. G. Paren ◽  
S. Cooper
Keyword(s):  
Sea Level ◽  
Thermal Regime ◽  
Sea Water ◽  
Water Movement ◽  
Freezing Point ◽  
Flow Line ◽  
Layer Structure ◽  
Hot Water ◽  
Lake Area ◽  
Ice Shelf

New data on the thermal regime of George VI Ice Shelf have been obtained by thermistor chains installed through the use of a hot-water drill. Twenty thermistors are used at each site, spaced close together at sea-level and at the base of the ice shelf, and farther apart elsewhere in the ice shelf and in the sea beneath. Based on earlier observations (Bishop and Walton 1981, fig. 7) that the 10 m temperature warms from around −10°C in the central melt-lake area of the ice shelf (from 70°45′ to 71°45′S) to around −2°C near the northern ice front (70°00′S), the thermistor chains were deployed at three sites (70°00′, 70°15′ and 70°30′S) along a presumed flow line. The observations show that as ice flows towards the northern ice front of George VI Ice Shelf, it becomes more temperate in character. Heat from the sea and from the percolation of melt water at the upper surface progressively warms the ice shelf. At mid-depth (the coldest level in the ice shelf) the recorded temperatures were −6°C off Moore Point (70°30′S), −4°C off Carse Point (70°15′S) and, near the northern ice front (70°00′S), between −1.6° and −1.8°C depending on the time of year. The ice-shelf temperatures near the ice front, warmer in mid-summer than the freezing point of fully saline sea-water, are most unusual. The only explanation of the high, fluctuating temperatures found 1 year after drilling is that the hole through the ice shelf was open, allowing unimpeded water movement. This implies that the ice shelf is also warmed by the percolation of sea-water, whose presence was confirmed by ice-core drilling to below sea-level. Confirmation of the presence of brine below sea-level in the ice shelf comes from geo-electrical investigations. A Schlumberger georesistivity array modelled the ice shelf as a simple two-layer structure, with ordinary glacier overlying highly conductive ice. This is consistent with the fact that no radio echoes have been received from the bottom of George VI Ice Shelf to the north of 70°09′S. A detailed analysis of the ice-shelf / ocean-temperature profiles was undertaken. This included an analysis of the fluctuation observed in mid-summer at the warmest site and the subsequent transition to a stable isothermal profile through the submerged part of the ice shelf.

The evolution of under-ice melt ponds, or double diffusion at the freezing point

1974 ◽  
Vol 64 (3) ◽  
pp. 507-528 ◽  
Author(s):  
Seelye Martin ◽  
Peter Kauffman
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Freezing Point ◽  
Salt Water ◽  
Ice Sheet ◽  
Water Layer ◽  
Double Diffusion ◽  
Theoretical Models ◽  
Interfacial Region ◽  
Ice Melt

In an experimental and theoretical study, we model a phenomenon observed in the summer Arctic, where a fresh-water layer at a temperature of 0°C floats both over a sea-water layer at its freezing point and under an ice layer. Our results show that the ice growth in this system takes place in three phases. First, because the fresh-water density decreases upon supercooling, the rapid diffusion of heat relative to salt from the fresh to the salt water causes a density inversion and thereby generates a high Rayleigh number convection in the fresh water. In this convection, supercooled water rises to the ice layer, where it nucleates into thin vertical interlocking ice crystals. When these sheets grow down to the interface, supercooling ceases. Second, the presence of the vertical ice sheets both constrains the temperatureTand salinitysto lie on the freezing curve and allows them to diffuse in the vertical. In the interfacial region, the combination of these processes generates a lateral crystal growth, which continues until a horizontal ice sheet forms. Third, because of theTandsgradients in the sea water below this ice sheet, the horizontal sheet both migrates upwards and increases in thickness. From one-dimensional theoretical models of the first two phases, we find that the heat-transfer rates are 5–10 times those calculated for classic thermal diffusion.

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