𝔖 Bobbio Scriptorium
✦   LIBER   ✦

The influence of diffusion in the external medium upon the determination of cytoplasmic diffusion coefficients

✍ Scribed by Søren Løvtrup; Kjell Hansson Mild; André Berglund


Publisher
John Wiley and Sons
Year
1970
Tongue
English
Weight
492 KB
Volume
76
Category
Article
ISSN
0021-9541

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

The exchange of isotopic water has been studied in ovarian eggs from three Anuran species (R. esculenta, R. pipiens and R. temporaria) by the automatic diver balance technique. The oocytes were treated with chemicals (digitonin, ethanol and formaldehyde) to remove the plasma membrane. The cytoplasmic diffusion coefficient for water was calculated with and without allowance for the influence of diffusion in the external medium. The former expedient was found necessary in order to obtain correct values. The chemical treatments gave different values, but there are sound reasons to believe that those obtained with digitonin (8.9, 15.3 and 10.8.10^−6^ cm^2^sec^−1^ for R. esculenta, R. pipiens and R. temporaria, respectively) are the correct ones. These results indicate that the rate of diffusion in the oocyte cytoplasm amounts to 50–75% of that of free diffusion.


📜 SIMILAR VOLUMES


Influence of External Magnetic Field on
✍ J. Dryzek; P. Golonka 📂 Article 📅 2002 🏛 John Wiley and Sons 🌐 English ⚖ 117 KB 👁 2 views

This paper presents Monte Carlo simulations of the positron diffusion process in a solid grain when an external magnetic field is applied. Our work has focused on the fraction of positrons, which reach the grain boundary because such a parameter can be observed in positron experiments. The simulatio

Comparison of methods for the determinat
✍ E. P. C. Mes; W. Th. Kok; H. Poppe; R. Tijssen 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 162 KB 👁 3 views

A comparison between various methods to determine diffusion coefficients of polymers in dilute solutions has been made. It is shown that Taylor dispersion analysis (TDA), dynamic light scattering (DLS), hydrodynamic chromatography (HDC), and size exclusion chromatography (SEC) can all be used to acc