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THE ELECTRICAL CONDUCTIVITY OF PURE PROTOPLASM
1Division of Pharmacology, Hygienic Laboratory, United States Public Health Service, Washington, D. C.
The Journal of General Physiology
|October 30, 2009
Summary
The electrical conductivity of slime mold protoplasm is similar to a dilute salt solution. Increased conductivity in seawater suggests protoplasm is permeable to electrolytes.
Area of Science:
- Biophysics
- Cell Biology
Background:
- Slime molds, like Brefeldia maxima, are valuable models for studying protoplasmic properties due to their composition.
- Understanding the electrical properties of protoplasm is crucial for elucidating cellular transport mechanisms.
Purpose of the Study:
- To measure the electrical conductivity of Brefeldia maxima plasmodium.
- To investigate the relationship between protoplasmic conductivity and its surrounding environment.
Main Methods:
- Electrical conductivity measurements of the slime mold plasmodium.
- Comparison of conductivity with standard saline solutions and the external medium.
Main Results:
- The electrical conductivity of Brefeldia maxima plasmodium approximates that of a 0.00145 N NaCl solution under normal conditions.
- Conductivity significantly increased when the slime mold was bathed in 1% seawater, exceeding that of the external fluid.
- The slime mold's conductivity was approximately 2.8 times higher than the liquid it developed in.
Conclusions:
- Preliminary findings support the hypothesis that slime mold protoplasm is permeable to electrolytes.
- The results suggest that protoplasm maintains an electrolyte equilibrium with its environment.
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