HEAT PRODUCTION BY THE EGGS OF ARBACIA PUNCTULATA DURING FERTILIZATION AND EARLY CLEAVAGE
نویسندگان
چکیده
منابع مشابه
Fertilization and the Temperature Coefficients of Oxygen Consumption in Eggs of Arbacia Punctulata
The eggs of A. punctulata have a high temperature coefficient in the resting state: Q(10) = 4.1. On fertilization and on cytolysis the temperature coefficient falls to less than half the resting value: Q(10) = 1.8 and 1.9 respectively. The factor by which oxygen consumption increases on fertilization is a variable, its magnitude depending on temperature as well as on egg species. It is nearly t...
متن کاملA Fine Structural Analysis of Cleavage Induction and Furrowing in the Eggs of Arbacia Punctulata
A fine structural study has been carried out on the various formed elements present before, during, and after the first cleavage division, not only in normally developing Arbacia eggs, but also in eggs which have been induced to cleave prematurely by high-pressure centrifugation. The aim has been to ascertain whether or not any of the morphologically identifiable components may be involved in i...
متن کاملThe Nucleic Acid of the Eggs of Arbacia Punctulata
Quantitative determinations of the phosphorus distribution in the eggs of a variety of species by Tschernorutzki (l), Massing (2), and Needham and Needham (3) have indicated the probable presence of nucleoproteins in unfertilized ova. Unfortunately, however, the presence of vitellins in such cells renders the exact interpretation of such analyses somewhat difficult since, with current methods o...
متن کاملThe Osmotic Properties of Living Cells (eggs of Arbacia Punctulata)
WE HAVE ATTEMPTED TO ANSWER THE QUESTION: How nearly ideal, as an osmometer, is the unfertilized Arbacia egg? The following conclusion have been reached: 1. Volumes can be measured accurately over a wide range of pressures since the cell is in general spherical and does not suffer deformation from its own weight or other factors. 2. The product of volume and pressure is approximately constant, ...
متن کاملHexokinase Activity from Eggs of the Sea Urchin Arbacia Punctulata
1. The hexokinase activity of homogenates of eggs and embryos of the sea urchin Arbacia punctulata has been measured. Expressed as micrograms glucose consumed at 20 degrees C., per hour per milligram of protein the following values were obtained: unfertilized eggs, 67; fertilized eggs, 72; 24 hour plutei, 94; 48 hour plutei, 226. The concentration of the enzyme in the eggs is small and may be c...
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ژورنال
عنوان ژورنال: The Biological Bulletin
سال: 1925
ISSN: 0006-3185,1939-8697
DOI: 10.2307/1536642