Superior Flexor Muscle Cells :: Biology Essays Research Papers

Effects of Extracellular Potassium Concentration on tissue layer Potentials in Crayfish Superior Flexor Muscle CellsIntracellular touchstone of tissue layer potentials in cells of the crayfish superficial flexor massiveness tail end reveal the effects of varying the extracellular submergences of potassium ion on the resting potential. Our results refer that at high extracellular potassium closenesss, the resting potential resembles that of the potassiums equalizer potential, and at low potassium concentrations, resting potential is less cerebrate to potassium equilibrium potential. We suggest that the equilibrium potential of other ions, in particular sodium, contribute more heavily to the resting potential when extracellular potassium concentration is low, which accounts for the resting potential having a less negative voltage than the potassium equilibrium potential. The determination of resting potential by the equilibrium potentials of numerous ions reduces the effect that concentration changes in any single ion will view on the resting potential, add stability to neural cell function even during changing environmental conditions.We tested the effect of extracellular potassium concentration on membrane potentials in the crayfish superficial flexor brawniness cells. We compared five several(predicate) extracellular concentrations of K+ and measured resting potentials by recording extracellularly and intracellulary, using an electrode that was inserted into the muscle via a micropipette. Our results confirm the relationship between voltage across the membrane and equilibrium potentials of the most prevalent ions that is stated by the Goldman Equation.Micropipettes were constructed from capillary tubes with tippytoe diameter of a fraction of a micron. A micropipette and holder were make full with 3M KCl use of this saturated solution ensured that intracellular K+ did not subdued from the cell up the pipette. The top of the holder, which conn ected to the Neuroprobe amplifier circuitry, contained an Ag/AgCl electrode to prevent the hydrolysis of water, which would have created bubbles of hydrogen gas that would interfere with current conduction.The crayfish superficial muscle was exposed by making a U-shaped cut in the abaxial carapace and removing the dorsal muscles, leaving only the ventral carapace, its attached muscles, and peradventure the nerve cord. This region was then placed in a minor plasticene dish covered with one of five crayfish Ringers solutions. Normal (1x) crayfish Ringers solution contained K+ = 5.4 mM and was used as a control the four experimental solutions contained K+ of .54 (.1x), 16.2 (3x), 54 (10x), and 162 (30x) mM respectively. Despite the non-uniformity of resume osmolarity, the proportion of K+ to Cl-, the other important diffusible ion, remained constant, satisfying the Donnan Equilibrium.