A METHOD OF STUDYING RESPIRATION
An apparatus is described which makes it possible to measure rapidly and accurately small amounts of CO2 given off by organisms of all kinds. The apparatus can also be used to measure photosynthesis.
ON THE DYNAMICS OF PHOTOSYNTHESIS
Osterhout, W. J. V., Haas, A. R. C.
Minute amounts of photosynthesis in marine plants can be accurately measured by adding a little phenolphthalein to the sea water, and observing changes in the color of the indicator. In the case of...
AN INDICATOR METHOD OF MEASURING THE CONSUMPTION OF OXYGEN
The blood of the horseshoe crab (Limulus) absorbs oxygen and turns blue when shaken in air. In the presence of certain organisms which consume oxygen it is quickly decolorized. By measuring the time...
COMPARATIVE STUDIES ON RESPIRATION : I. INTRODUCTION.
A series of investigations on respiration with improved quantitative methods has been commenced. The first of these are here described. They show that when anesthetics are employed in sufficient...
A COMPARATIVE STUDY OF PERMEABILITY IN PLANTS
Quantitative studies on Laminaria (a brown alga), Ulva (a green alga), Rhodymenia (a red alga), and Zostera (a flowering plant) show that the behavior of these plants, in respect to changes in...
THE TEMPERATURE COEFFICIENT OF PHOTOSYNTHESIS
Osterhout, W. J. V., Haas, A. R. C.
The temperature coefficient of photosynthesis in Ulva (between 17° and 27°C.) is 1.81. This may be explained by assuming that the process involves a light reaction with a low coefficient followed...
A COMPARISON OF PERMEABILITY IN PLANT AND ANIMAL CELLS
Quantitative studies show a striking agreement between frog skin and plant tissues in respect to certain important aspects of permeability, antagonism, injury, recovery, and death.
DECREASE OF PERMEABILITY AND ANTAGONISTIC EFFECTS CAUSED BY BILE SALTS
Sodium taurocholate is able to produce a decrease in permeability and to antagonize NaCl. This confirms the hypothesis that antagonistic relations can be predicted from studies on the permeability of...
ANTAGONISM BETWEEN ALKALOIDS AND SALTS IN RELATION TO PERMEABILITY
Certain alkaloids which decrease permeability are able to antagonize NaCl. In this respect they resemble salts which decrease permeability, for it has been shown that such salts antagonize NaCl.
A THEORY OF INJURY AND RECOVERY : I. EXPERIMENTS WITH PURE SALTS.
In addition to the Correction in Vol. iii, No. 3, January 20, 1921, on page 149, Vol. iii, No. 2, November 20, 1920, line 13, for 92.57 read 89.10; page 154, lines 15, 28, and 32, for O read O+10;...
A THEORY OF INJURY AND RECOVERY : I. EXPERIMENTS WITH PURE SALTS.
On page 150, Vol. iii, No. 2, November 20, 1920, line 18, for The resistance after, etc., read The resistance due to A and M after, etc.; line 20, of the same page, equation (4) should read as...
A THEORY OF INJURY AND RECOVERY : I. EXPERIMENTS WITH PURE SALTS.
1. Laminaria exposed for a short period to 0.52 M NaCl loses a part of its electrical resistance but recovers it completely when replaced in sea water. When the period is lengthened recovery is...
An electrical current passing through a living plant flows partly through the cell wall and partly through the protoplasm. The relative amounts of these two portions of the current can be calculated....
A THEORY OF INJURY AND RECOVERY : II. EXPERIMENTS WITH MIXTURES.
1. The equations which serve to predict the injury of tissue in 0.52 M NaCl and in 0.278 M CaCl2 and its subsequent recovery (when it is replaced in sea water) also enable us to predict the behavior...
A THEORY OF INJURY AND RECOVERY : III. REPEATED EXPOSURES TO TOXIC SOLUTIONS.
Tissues of Laminaria transferred from sea water to solutions of pure salts, and thence to other solutions of pure salts, or to sea water, behave in a manner which can be predicted by means of the...
DIRECT AND INDIRECT DETERMINATIONS OF PERMEABILITY
1. Methods are described for obtaining cell sap from Nitella without contamination. 2. Tests of the cell sap show that in a balanced solution of NaNO3 plus Ca(NO3)2 there is a slow penetration of NO3...
SOME ASPECTS OF SELECTIVE ABSORPTION
1. A mechanism exists in Valonia which prevents certain substances (Na, Mg, Ca, SO4) from reaching as high a concentration inside the cell as in the sea water which surrounds it. 2. A trapping...
EXOSMOSIS IN RELATION TO INJURY AND PERMEABILITY
The time curve expressing the increase in the permeability of Nitella during the progress of death is practically the same whether derived from measurements of exosmosis or of electrical resistance.
ON THE IMPORTANCE OF MAINTAINING CERTAIN DIFFERENCES BETWEEN CELL SAP AND EXTERNAL MEDIUM
A striking difference exists between the internal and external solution in the case of Valonia macrophysa. If this difference is abolished by placing cells in their own sap most of them quickly die....
CONTRASTS IN THE CELL SAP OF VALONIAS AND THE PROBLEM OF FLOTATION
Osterhout, W. J. V., Dorcas, M. J.
The marine alga Valonia macrophysa contains in its cell sap K and Na in the proportion of 5.72 to 1. In a form regarded as closely related, Valonia ventricosa, growing in similar environment, the...
IS LIVING PROTOPLASM PERMEABLE TO IONS?
The experiments indicate that under normal conditions little or no H2S enters the cell sap of Valonia macrophysa except as undissociated molecules.
IS LIVING PROTOPLASM PERMEABLE TO IONS?
On page 138, Vol. viii, No. 2, September 18, 1925, in line 4 from bottom, in place of (50) (5.4) = 2.7 read See PDF for Equation. In the next line, in place of 52.7 read 52.9. On page 139, in line 3...
THE PENETRATION OF CO2 INTO LIVING PROTOPLASM
Osterhout, W. J. V., Dorcas, M. J.
The experiments indicate that little or no CO2 enters normal cells of Valonia except in the form of undissociated molecules. Whenever the interior of a cell is more acid than the surrounding medium...
SOME ASPECTS OF BIOELECTRICAL PHENOMENA
It is pointed out that there are great advantages in using single cells instead of tissues in the study of bioelectrical phenomena. Certain bioelectrical phenomena are discussed in relation to the...
DISSIMILARITY OF INNER AND OUTER PROTOPLASMIC SURFACES IN VALONIA
Osterhout, W. J. V., Damon, E. B., Jacques, A. G.
The protoplasm of Valonia macrophysa forms a delicate layer, only a few microns in thickness, which contains numerous chloroplasts and nuclei. The outer surface is in contact with the cell wall, the...
PROTOPLASMIC ASYMMETRY IN NITELLA AS SHOWN BY BIOELECTRIC MEASUREMENTS
Osterhout, W. J. V., Harris, E. S.
Using multinucleate cells of Nitella 2 or 3 inches in length it is possible to kill one end with chloroform without producing at the other any immediate alteration which can be detected by our...
NOTE ON THE NATURE OF THE CURRENT OF INJURY IN TISSUES
Osterhout, W. J. V., Harris, E. S.
Leading off from two places on the same cell (of Nitella) with 0.001 M KCl we observe that a cut produces only a temporary negative current of injury. If we lead off with 0.001 M KCl from any cell to...
NOTE ON THE NATURE OF THE CURRENT OF INJURY IN TISSUES
Osterhout, W. J. V., Harris, E. S.
On page 48 to 54, Vol. 13, No. 1, September 20, 1929, through a mistake in printing the image of the string in Figs. 2, 6, 7, 9, 12, and 14 appears double. To obviate any misunderstanding it should...
THE KINETICS OF PENETRATION : I. EQUATIONS FOR THE ENTRANCE OF ELECTROLYTES
When the only solute present is a weak acid, HA, which penetrates as molecules only into a living cell according to a curve of the first order and eventually reaches a true equilibrium we may regard...
THE KINETICS OF PENETRATION : I. EQUATIONS FOR THE ENTRANCE OF ELECTROLYTES
On page 267, Vol. 13, No. 2, November 20, 1929, the bottom line should read See PDF for Equation On page 275, the fifth line should read where PM + PAK = 1 this becomes See PDF for Equation
NEGATIVE VARIATIONS IN NITELLA PRODUCED BY CHLOROFORM AND BY POTASSIUM CHLORIDE
Osterhout, W. J. V., Hill, S. E.
The results of applying chloroform and KCl to Nitella indicate that a negative variation may be started whenever it is possible to set up along the protoplasm a gradient of potential difference...
THE CONCENTRATION EFFECT WITH VALONIA: POTENTIAL DIFFERENCES WITH CONCENTRATED AND DILUTED SEA WATER
Damon, E. B., Osterhout, W. J. V.
The P.D. between the interior of a cell of Valonia macrophysa and concentrated or diluted sea water applied externally is given by the empirical equation: See PDF for Equation where P.D.s.w. is the...
SALT BRIDGES AND NEGATIVE VARIATIONS
Osterhout, W. J. V., Hill, S. E.
A negative variation in Nitella is unable to pass a spot killed by chloroform but can set up a negative variation beyond this spot when a salt bridge is put around it. It can likewise set up a...
CALCULATIONS OF BIOELECTRIC POTENTIALS : I. EFFECTS OF KCl AND NaCl ON NITELLA
The P.D. of 0.01 M vs. 0.001 M KCl (concentration effect) in Nitella is 54.7 mv. and that of NaCl is 20.9 mv. The P.D. of 0.01 M NaCl vs. 0.01 M KCl is 82.9 mv. If we assume that diffusion potentials...
THE KINETICS OF PENETRATION : II. THE PENETRATION OF CO2INTO VALONIA
Jacques, A. G., Osterhout, W. J. V.
The rate of penetration of CO2 into living cells of Valonia has been studied at high and low pH values. The time curve of penetration appears to be of the first order but with a "velocity constant"...
THE ACCUMULATION OF ELECTROLYTES : I. THE ENTRANCE OF AMMONIA INTO VALONIA MACROPHYSA
Cooper, Wm. C., Osterhout, W. J. V.
When 0.005 M NH4Cl is added to sea water containing cells of Valonia macrophysa ammonia soon appears in the sap and may reach a concentration inside over 40 times as great as outside. It appears to...
THE ACCUMULATION OF ELECTROLYTES : II. SUGGESTIONS AS TO THE NATURE OF ACCUMULATION IN VALONIA
It is suggested that K enters chiefly as KOH, whose thermodynamic potential (proportional to the ionic activity product (aK) (aOH)) is greater outside than within. As this difference is maintained by...
THE KINETICS OF PENETRATION : III. EQUATIONS FOR THE EXCHANGE OF IONS
Equations are given for a variety of cases when ions of the same sign are exchanged between the interior of a living cell and the external solution.
THE ACCUMULATION OF ELECTROLYTES : III. BEHAVIOR OF SODIUM, POTASSIUM, AND AMMONIUM IN VALONIA
Jacques, A. G., Osterhout, W. J. V.
When 0.001 M NH4Cl is added to sea water containing Valonia macrophysa there seems to be a rapid penetration of undissociated NH3 (or NH4OH) which raises the pH value of the sap so that the...
THE DEATH WAVE IN NITELLA : III. TRANSMISSION
Osterhout, W. J. V., Hill, S. E.
Cutting a cell of Nitella sets up a series of rapid electrical responses, transmitted at a rate too rapid to be measured by means of our records. These are followed by slower responses whose speed...
ELECTRICAL VARIATIONS DUE TO MECHANICAL TRANSMISSION OF STIMULI
Osterhout, W. J. V., Hill, S. E.
Mechanical stimulation of Nitella often produces responses resembling propagated negative variations but traveling faster and going past a killed spot. They appear to result from a mechanical...
THE KINETICS OF PENETRATION : III. EQUATIONS FOR THE EXCHANGE OF IONS
In Vol. 14, No. 2, November 20, 1930, page 283, the last two lines (above footnotes) should read See PDF for Equation
THE PRODUCTION AND INHIBITION OF ACTION CURRENTS BY ALCOHOL
Osterhout, W. J. V., Hill, S. E.
Suitable concentrations of ethyl alcohol (1 to 1.5 M) applied to a spot on a cell of Nitella lower the P.D. enough to cause action currents. The alcohol then suppresses action currents arriving from...
THE ACCUMULATION OF ELECTROLYTES : IV. INTERNAL VERSUS EXTERNAL CONCENTRATIONS OF POTASSIUM
Jacques, A. G., Osterhout, W. J. V.
Lowering the potassium in the sea water from 0.011 M to 0.006 M caused an exit of potassium from cells of Valonia macrophysa. Sodium continued to penetrate and the ratio K ÷ Na fell off. The cells...
THE ACCUMULATION OF ELECTROLYTES : V. MODELS SHOWING ACCUMULATION AND A STEADY STATE
Osterhout, W. J. V., Stanley, W. M.
Inasmuch as attempts to explain accumulation by the Donnan principle have failed in the case of Valonia, a hypothesis of the steady state has been formulated to explain what occurs. In order to see...
THE KINETICS OF PENETRATION : V. THE KINETICS OF A MODEL AS RELATED TO THE STEADY STATE
An organic potassium salt, KG, passes from an aqueous phase, A, through a non-aqueous layer, B, into a watery solution, C. In C it reacts with CO2 to form KHCO3. The ionic activity product (K) (G) in...
ANESTHESIA IN ACID AND ALKALINE SOLUTIONS
Osterhout, W. J. V., Hill, S. E.
The action of distilled water in producing anesthesia (loss of response to electrical stimulation) in Nitella is hastened by the addition of acid and alkali and retarded by the addition of calcium....
ANESTHESIA PRODUCED BY DISTILLED WATER
Osterhout, W. J. V., Hill, S. E.
Cells of Nitella flexilis Ag. lose their power to respond to ordinary electrical stimulation after 2 or 3 days in distilled water. It returns after a day or so when they are replaced in their normal...
REVERSIBLE LOSS OF THE POTASSIUM EFFECT IN DISTILLED WATER
Osterhout, W. J. V., Hill, S. E.
Not only does distilled water take away the irritability of Nitella but it also changes its behavior toward potassium. In normal cells potassium is strongly negative to sodium but after sufficient...
THE KINETICS OF PENETRATION : VI. SOME FACTORS AFFECTING PENETRATION
Osterhout, W. J. V., Kamerling, S. E., Stanley, W. M.
Some of the factors affecting penetration in living cells may be advantageously studied in models in which the organic salts KG and NaG diffuse from an aqueous solution A, through a non-aqueous layer...
KINETICS OF PENETRATION : VII. MOLECULAR VERSUS IONIC TRANSPORT
Osterhout, W. J. V., Kamerling, S. E., Stanley, W. M.
In some living cells the order of penetration of certain cations corresponds to that of their mobilities in water. This has led to the idea that electrolytes pass chiefly as ions through the...
THE KINETICS OF PENETRATION : VIII. TEMPORARY ACCUMULATION
Osterhout, W. J. V., Kamerling, S. E.
A model is described which throws light on the mechanism of accumulation. In the model used an external aqueous phase A is separated by a non-aqueous phase B (representing the protoplasm) from the...
THE ACCUMULATION OF ELECTROLYTES : VI. THE EFFECT OF EXTERNAL pH
Jacques, A. G., Osterhout, W. J. V.
It would be natural to suppose that potassium enters Valonia as KCl since it appears in this form in the sap. We find, however, that on this basis we cannot predict the behavior of potassium in any...
NATURE OF THE ACTION CURRENT IN NITELLA : I. GENERAL CONSIDERATIONS
The outstanding features of the action curve in Nitella are explained as due to the movement of potassium ions accompanied by increase of permeability. This may be useful as a working hypothesis...
THE KINETICS OF PENETRATION : IX. MODELS OF MATURE CELLS
Kamerling, S. E., Osterhout, W. J. V.
To imitate cells which have ceased to grow we have made models in which artificial sap is separated from the external solution by a non-aqueous layer (representing the protoplasm). A stream of CO2 is...
POSITIVE VARIATIONS IN NITELLA
Osterhout, W. J. V., Hill, S. E.
The reversible electrical variations hitherto described for plants and animals consist in a reversible loss of positive potential at a stimulated spot by which it becomes more negative. In this paper...
NATURE OF THE ACTION CURRENT IN NITELLA : II. SPECIAL CASES
Hill, S. E., Osterhout, W. J. V.
The action curve involves four movements each of which shows considerable variation. These variations can be accounted for on the assumption that the action curve is due to the movement of potassium...
NATURE OF THE ACTION CURRENT IN NITELLA : III. SOME ADDITIONAL FEATURES
Osterhout, W. J. V., Hill, S. E.
Several forms of the action curve are described which might be accounted for on the ground that the outer protoplasmic surface shows no rapid electrical change. This may be due to the fact that the...
MECHANICAL RESTORATION OF IRRITABILITY AND OF THE POTASSIUM EFFECT
Hill, S. E., Osterhout, W. J. V.
Treatment of Nitella with distilled water apparently removes from the cell something which is responsible for the normal irritability and the potassium effect, (i.e. the large P.D. between a spot in...
RESTORATION OF THE POTASSIUM EFFECT BY MEANS OF ACTION CURRENTS
Osterhout, W. J. V., Hill, S. E.
Treatment with distilled water removes from Nitella the ability to give the large potential difference between 0.01 M KCl and 0.01 M NaCl which is known as the potassium effect. The potassium effect...
THE KINETICS OF PENETRATION : XI. ENTRANCE OF POTASSIUM INTO NITELLA
Jacques, A. G., Osterhout, W. J. V.
The rate of entrance of potassium into Nitella flexilis has been investigated, and it has been shown that (a) at the concentrations studied the rate is independent of the external pH between 6 and 8...
CHEMICAL RESTORATION IN NITELLA : I. AMMONIA AND SOME OF ITS COMPOUNDS
The potassium effect in Nitella (the high P.D. observed in leading off from a spot in contact with 0.01 M KCl to one in contact with 0.01 M NaCl) and the irritability can be removed by placing cells...
THE ACCUMULATION OF ELECTROLYTES : VIII. THE ACCUMULATION OF KCl IN MODELS
Osterhout, W. J. V., Kamerling, S. E.
Models are described in which KCl enters until its chemical potential becomes much greater inside than outside. The energy needed to accomplish this comes from the chemical reactions occurring in the...
PACEMAKERS IN NITELLA : I. TEMPORARY LOCAL DIFFERENCES IN RHYTHM
Hill, S. E., Osterhout, W. J. V.
A series of negative variations passing along the cell may reach a region where only every other variation registers. This condition may be temporary. It would seem to depend on a local change in the...
CHEMICAL RESTORATION IN NITELLA : II. RESTORATIVE ACTION OF BLOOD
Cells of Nitella exposed to distilled water lose their ability to produce action currents and to distinguish electrically between sodium and potassium. This ability was quickly restored by exposure...
CHANGES OF APPARENT IONIC MOBILITIES IN PROTOPLASM : I. EFFECTS OF GUAIACOL ON VALONIA
In normal cells of Valonia the order of the apparent mobilities of the ions in the non-aqueous protoplasmic surface is K > Cl > Na. After treatment with 0.01 M guaiacol (which does not injure the...
CHANGES OF APPARENT IONIC MOBILITIES IN PROTOPLASM : II. THE ACTION OF GUAIACOL AS AFFECTED BY pH
The normal P.D. across the protoplasm of Valonia macrophysa is about 10 mv. negative (inwardly directed). On adding 0.01 M guaiacol to the sea water the P.D. becomes positive and then slowly returns...
CALCULATIONS OF BIOELECTRIC POTENTIALS : II. THE CONCENTRATION POTENTIAL OF KCl IN NITELLA
Hill, S. E., Osterhout, W. J. V.
Cells of Nitella have been studied which behave differently from those described in earlier papers. They show unexpectedly large changes in P.D. with certain concentrations of KCl. This is due to the...
THE ACCUMULATION OF ELECTROLYTES : X. ACCUMULATION OF IODINE BY HALICYSTIS AND VALONIA
Jacques, A. G., Osterhout, W. J. V.
Analyses of the sap of Halicystis Osterhoutii and of Valonia macrophysa for iodide indicate accumulations of the order of 1000 to 10,000-fold in the first case, and 40 to 250-fold in the second case....
EFFECTS OF POTASSIUM ON THE POTENTIAL OF HALICYSTIS
Sea water in which sodium has been replaced by potassium produces about the same degree of negativity in Halicystis and in Valonia. With increasing dilution of this sea water up to 1 ÷ 16 the degree...
CHANGES OF APPARENT IONIC MOBILITIES IN PROTOPLASM : III. SOME EFFECTS OF GUAIACOL ON HALICYSTIS
Lowering the pH of sea water from 8.2 to 6.4 lowers the positive P.D. of Halicystis reversibly (this does not happen with Valonia). Exposure to sea water at pH 6.4 does not affect the apparent...
THE ACCUMULATION OF ELECTROLYTES : XI. ACCUMULATION OF NITRATE BY VALONIA AND HALICYSTIS
Jacques, A. G., Osterhout, W. J. V.
The nitrate concentration in the sap of Valonia macrophysa, Kütz., is at least 2000 times that of the sea water, and in Halicystis Osterhoutii, Blinks and Blinks, at least 500 times that of the sea...
CALCULATIONS OF BIOELECTRIC POTENTIALS : IV. SOME EFFECTS OF CALCIUM ON POTENTIALS IN NITELLA
Osterhout, W. J. V., Hill, S. E.
In Nitella the substitution of KCl for NaCl changes the P.D. in a negative direction. In some cases this change is lessened by adding solid CaCl2 to the solution of KCl. This may be due to lessening...
In Nitella, as in Halicystis, guaiacol increases the mobility of Na+ in the outer protoplasmic surface but leaves the mobility of K+ unaffected. This differs from the situation in Valonia where the...
INCREASED IRRITABILITY IN NITELLA DUE TO GUANIDINE
Guanidine applied to Nitella may lower the threshold of E.M.F. required to produce electrical stimulation and may give rise to trains of action currents. Its effect thus appears to be somewhat...
CHEMICAL RESTORATION IN NITELLA : IV. EFFECTS OF GUANIDINE
Leaching in distilled water may remove irritability and the potassium effect in Nitella but both of these may be restored by appropriate treatment with guanidine.
Osterhout, W. J. V., Hill, S. E.
The action curve in Chara seems to depend (as in Nitella) on the outward movement of K+ from the sap. Presumably the increase in permeability in the inner protoplasmic surface and the outward...
DIFFUSION POTENTIALS IN MODELS AND IN LIVING CELLS
The behavior of guaiacol resembles that of certain protoplasmic surfaces to such an extent that it can be advantageously used in models designed to imitate certain aspects of protoplasmic behavior....
PACEMAKERS IN NITELLA : III. ELECTRICAL ALTERNANS
An electrical impulse traveling along a Nitella cell may produce a complete or a partial response. The two kinds of response may occur in regular alternation. The partial response varies greatly and...
NATURE OF THE ACTION CURRENT IN NITELLA : V. PARTIAL RESPONSE AND THE ALL-OR-NONE LAW
When a stimulus arrives before recovery is complete there may be no response or only a partial response. A typical response appears to involve an immediate loss of potential at the inner protoplasmic...
In Nitella, Chara, Hydrodictyon, and Valonia the inner and outer non-aqueous protoplasmic surface layers can be separated by certain plasmolytic agents which penetrate the outer surface more rapidly...
A MODEL OF THE POTASSIUM EFFECT
The protoplasm of certain cells is able to distinguish electrically between K+ and Na+. This has been called the potassium effect. This is illustrated by experiments with Nitella. When 0.01 M KCl...