Membrane disintegration

Ad. 4. Alteration of anatomical features. Finally, several studies have attempted to manipulate the macroscopic features of muscle/meat tissue in order to verify or disprove the intra-/extra-cellular model. Efforts have been made to disrupt cell membranes by glycerination and DMSO treatment in order to make assessment of the potential role of membranes possible.30,40,41 All these studies showed unaltered relaxation behaviour upon membrane disintegration, which suggests that intact cell membranes in themselves are not necessary for a non-mono-exponential relaxation. Irrelevance of membranes... 

The enterocytes of the small intestine can be isolated and used for study of intracellular aspects of intestinal lipid transport like triglyceride synthesis [52]. The disappearance of the mucus barrier during isolation of the epithelial cells results in plasma membrane disintegration and loss of cellular integrity when the cells are exposed to bile salts. As is the case for brush border vesicles, the system of isolated cells does not allow study of interaction between enterocytes and lipids dispersed in a form that resembles physiological conditions, i.e. solubilized in mixed bile salt micelles. 

Prophase - In prophase, the replicated chromosomes condense into the typical metaphase chromosome structures so often pictured. The nuclear membrane disintegrates, and the mitotic spindle forms. The spindle consists of contractile microtubules that pull pairs of chromatids apart so that the daughter cells will each receive identical sets of chromosomes. 

As the K efflux from plant tissue demonstrates membrane disintegration in particular, Nifontova et al. (1995) investigated the permeability of lichen membranes as a result of gamma radiation. Thalli of different lichen species were irradiated for this purpose. The membrane permeability in irradiated thalli of Cladonia arbuscula, Cetraria islandica and Hypogymnia physodes increased considerably in comparison with untreated control thalli. The K efflux from H. physodes thalli intensified with an increase of the radiation dose whereas no correlation was obtained for the K efflux and the radiation dose in C. arbuscula and C. islandica. The N content in Peltigera aphtosa appeared, however, to remain stable under acute gamma radiation. 

Nuclear membrane persists during mitosis. Nuclear membrane disintegrates by anaphase. Nuclear division occurs within the cyst. 

For both gel contents and qualitative solubility tests, membrane samples of similar thickness are immersed in the respective solvent, and kept at a fixed temperature for a fixed period of time, typically a few days. After the test, the membrane sample is dried and weighed to give ( residual- If the Solution is stirred, care must be taken that the membrane is not hit by the stirrer to prevent mechanical degradation. For this purpose, the membrane samples can be protected by a sieve or wire mesh. In case the membrane disintegrates the solution can be filtered and the dissolved portion can be determined by evaporation of the solvent. 

The falling pH value and the high temperature cause protein denaturation. Soluble proteins precipitate and scatter light. Consequently, the meat appears paler in spite of the unchanged myoglobin content. At the same time, cell membranes disintegrate and water loss increases. In fact, PSE pork incurs up to 15% drip loss in 3 days and normal meat only ca. 4%. 

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