The Respiration of Pteroides Griseum (Bohadsch) a Pennatulid Coelenterate

1967 ◽  
Vol 46 (1) ◽  
pp. 97-104
Author(s):  
A. E. BRAFIELD ◽  
G. CHAPMAN

1. The respiration of the pennatulid Pteroides griseum has been investigated by means of a continuous-flow polarographic respirometer and a strip-chart recorder. 2. The rate of oxygen consumption bears the same exponential relation to body weight as in more advanced phyla, and is markedly greater in expanded specimens than in contracted ones. 3. It is suggested that contracted specimens consume oxygen almost exclusively through the ectoderm but that in expanded specimens at least two-thirds of the total oxygen consumed enters through the endoderm. 4. Several sources of evidence confirm that the water within the enteron is poorly oxygenated. Rhythmically fluctuating records of the oxygen concentration of water which has flowed past expanded specimens are the result of periodic expulsions of some of this relatively deoxygenated enteric water. 5. The irrigation of the enteron is very probably brought about by peristaltic waves of contraction which pass along the length of the animal.

1980 ◽  
Vol 88 (1) ◽  
pp. 367-374
Author(s):  
A. E. BRAFIELD

Oxygen consumption by Calliactis parasitica, measured in a continuousflow polarographic respirometer, yielded a slope of 0·92 when plotted against body weight on log scales. This high value is discussed in terms of the sea anemone's basically laminate nature. Strip-chart records of the oxygen concentration of water which had just passed a specimen of Calliactis commonly showed rhythmic fluctuations, either of low amplitude and high frequency or high amplitude and low frequency (mean cycle lengths 11 and 34 min respectively). The fluctuations are explained in terms of rhythmic muscular contractions which irrigate the enteron for respiratory purposes. Analysis of the slow fluctuations indicates that the endoderm is responsible for about 18% of the total oxygen consumption. The oxygen concentration of water in the enteron, measured and recorded continuously, was 4–27% of the air-saturation level. These strip chart records also frequently showed rhythmic fluctuations (mean cycle length 12 min), apparently resulting from the muscular contractions.


1951 ◽  
Vol 28 (4) ◽  
pp. 492-507 ◽  
Author(s):  
C. ELLENBY

1. Male Ligia oceanica were used in an investigation of the relationship of body size to rate of oxygen consumption and pleopod beat. 2. Animals varied in weight from 0.04 to 1.03 g. and from 0.95 to 3.1 cm. in length. 3. Body shape does not change significantly over the size range, for length and breadth both increase at the same rate, and pleopod dimensions bear a constant relation to body length. 4. Specific gravity also is constant, for the relation of body weight to the cube of body length shows no trend with increasing size. 5. Oxygen consumption per gram decreases with increasing size and is proportional to the -0.274 Power of body weight. Total oxygen consumption is therefore proportional to the 0.726 power of body weight; but this value does not differ significantly from two-thirds. 6. As shape is constant, surface area is proportional to the square of a linear dimension. It is shown that oxygen consumption per unit of length2 is constant over the size range. Although body length was measured far less accurately than body weight it is shown that it assesses ‘body size’ more accurately. 7. Rate of pleopod beat was measured at 15 and 25°C.; it decreases with the size of the animal. At 15°C. time per beat varies as the 0.66 power of body length, and at 25°C. as the 0.59 power; neither of these values differs significantly from 0.5. Despite the fact that pleopod movement is heavily damped, the rate therefore varies like that of a pendulum. 9. The workof Fox (1936-9) and Fox et al. (1937a)on the rate of oxygen consumption of animals from cold and warmer seas and from different habitats is considered. It is suggested that many of their comparisons are invalidated by differences in body size of the animals concerned, and that, in relation to environment, no basis, theoretical or experimental, has been established for a distinction between ‘nonlocomotory’ and ‘activity’ metabolism.


1993 ◽  
Author(s):  
David Hammen ◽  
Travis Moebes ◽  
Robert Shelton ◽  
Robert Savely

1968 ◽  
Vol 48 (2) ◽  
pp. 427-434
Author(s):  
A. E. BRAFIELD

1. The oxygen consumption of the echiuroid Bonellia viridis has been investigated by means of a continuous-flow polarographic respirometer. 2. The general rate of oxygen consumption per unit dry weight is similar to that characteristic of polychaetes, and declines exponentially with increasing body size. 3. The rate of oxygen consumption rises in the light and falls again if darkness is restored. 4. The oxygen consumption of the isolated proboscis plus that of the isolated body region corresponds closely to that of the entire animal. 5. The oxygen consumption per unit dry weight of the proboscis is considerably higher than that of the body region. 6. The oxygen consumption of an isolated body region increases in the presence of light, but that of an isolated proboscis does not. 7. These findings are discussed in relation to the biology of the animal, observed muscular activity, and the occurrence of the pigment bonellin.


PEDIATRICS ◽  
1967 ◽  
Vol 39 (5) ◽  
pp. 724-732
Author(s):  
John C. Sinclair ◽  
Jon W. Scopes ◽  
William A. Silverman

Oxygen consumption of 92 normally grown newborn babies of birth weight 750 to 3,940 gm has been expressed in terms of various metabolic reference standards in order to identify any systematic variation in expression of metabolic rate that is introduced by these bases of reference in the newborn population. It is postulated that differences in body composition comprise a contributory factor to the variation among newborn babies in rate of oxygen consumption per kilogram body weight. The predictive error from a mean value is increased if surface area, body weight, or fat-free body weight is substituted for body weight as a metabolic reference standard. By taking into account known changes in body composition of the fetus with increasing maturity, a compartment representing the active tissue mass is calculated. This corresponds closely to body weight minus extracellular fluid and includes fat. Rate of oxygen consumption is proportional to the size of this compartment over the range of body weights studied. Implications are discussed as to the metabolic rate of adipose tissue in the newborn and body composition among undergrown babies.


1975 ◽  
Vol 21 (8) ◽  
pp. 1107-1112 ◽  
Author(s):  
Richard Passey ◽  
Ronald L Gillum ◽  
Mary Louise Giles ◽  
John B Fuller

Abstract We evaluated 16 claims made by Beckman Instruments, Inc. for its Enzyme Analyzer (System TR), under a rigid written protocol for the Product Evaluation Subcommittee of the Standards Committee of the College of American Pathologists. We found the following to be within the company's specifications: (a) accuracy and precision of the temperature control; (b) accuracy and precision of the sample and reagent pipets; (c) instrument precision, both within-run and between-day; (d) carry-over from a sample with activity > 1000 U/liter; (e) instrument-to-instrument variation; (f) analytical linearity; (g) analysis time; (h) correlation of the instrumentprinted answer with the activity calculated manually from a strip-chart recorder; (i) precision of the instrument's built-in electronic "standard"; (j) effectiveness of the over-range indicators; and (k) correlation between results of these enzyme assay methods and those for kinetic methods used in our laboratory. The instrument performed well.


Author(s):  
R. C. Newell ◽  
H. R. Northcroft

The rate of cirral beat of Balanus balanoides is related to the logarithm of the body weight as an exponential function. In any one animal, there is little effect of temperature on cirral activity between 7·5° and 10° C. Between 10° and 20° C, however, there is a rapid increase in cirral beat with temperature followed by a fall at temperatures above 20° C.Balanus balanoides exhibits a fast, medium and zero rate of oxygen consumption. These rates of oxygen consumption correspond with (a) normal cirral beating, (b) ‘testing’ activity with no cirral movement, and (c) with the closure of the mantle cavity. Both of the possible levels of oxygen uptake are related to the logarithm of the body weight in a logarithmic fashion over the temperature range 7·5°–22·5° C. Temperature affects the two rates of oxygen consumption differently. In the slower rate (rate B) there is an increase in the rate of oxygen consumption between 7·5° and 14° C but there is no significant increase in the rate of oxygen consumption between 14° and 22·5 C°.


1971 ◽  
Vol 15 ◽  
pp. 254-265 ◽  
Author(s):  
G.W. Martin ◽  
A.S. Klein

A system, has been designed and tested for rapid energy dispersive diffractometry and simultaneous fluorescence analysis. A turntable composed of the sample chamber with attached air-cooled x-ray tube allows the 2θ angle to be varied with respect to the stationary Si(Li) detector. Data for most analyses can be obtained in one minute per sample. Results are stored in the memory of a multichannel analyzer and are read out on a CRT, strip chart recorder or tabulated in digital format by a computer.


1977 ◽  
Vol 16 (06) ◽  
pp. 205-213
Author(s):  
H. DaCosta ◽  
B. A. Bagwe

Summary128 control, thyrotoxic, hypothyroid and goitrous euthyroid children were administered 1–2 μCi Na 131I orally and studied in a shadow-shield whole-body counter. 48-hr whole-body counts permitted the differentiation of the first 3 groups (p < 0.005). Ratio of extrathyroid:excreted 131I was 3 times greater in thyrotoxics than in goitrous euthyroids, but the thyroid:extrathyroid ratio was 3 times greater in the latter group. The whole-body profile scan obtained at 48 hr on an attached strip chart recorder, revealed activity not only in the thyroid but even lower down in the vicinity of the knees and feet.


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