Narcosis ciliates Essay Example | Topics and Well Written Essays - 1500 words

Narcosis ciliates - Essay Example This movement propels the cell perpendicular to the orientation of the cilia. In contrast, the longer flagellum, usually one or two, moves in an undulating manner, moving successive waves from the base to the tip in the process. As such, it propels the cell to move parallel to the flagellum’s orientation. On the other hand, microvilli are non-motile appendage with no internal structure supporting it (Reece, et al., 2011). The loss of activity of cilia, resulting to loss of cellular motility, is termed ciliate narcosis. This can be induced by different living conditions and substances to which it is exposed to, such as low temperature (Jackson, Goggin and Lucas, 2012), calcium (Nakanaka, Tanaka and Oosawa, 1984), magnesium and protein (Adshead, et al., 1975) concentrations, as well as the presence of certain substances, such as theophylline, bromhexine, ambroxol, terpin hydrate, mercaptoethanesulfonat-sodium, amrinon, salbutamol, tetracosactid-hexaacetate, histamine, phenol and nitric oxide (Graf, Graf and Wenz, 1999). In addition, a study using tracheal cells in vitro, showed that ciliary beat frequency was increased at low ethanol concentrations (0. 01 to 0. 1%), unchanged at (0. 5 to 1%), and decreased above 2% (Maurer and Liebman, 1988). Moreover, even if it does not penetrate the cellular membrane, the presence of glycerol in the culture can make cellular surroundings viscous, making it more difficult for cilia to move (Negus, 1949). Alcohols are amphiphatic molecules primarily composed of alkane (CH3) and hydroxyl (OH) moieties, such that the simplest alcohol is methane (CH3OH). When the hydrocarbon portion becomes longer, as in the case of ethanol (2 Cs), propranol (3 Cs) and butanol (4 Cs), the alcohol becomes effectively more hydrophobic. A compound similar to alcohols, propranolol in particular, is glycerol, which has hydroxyl group attached to each of the three carbon atoms (Masterton and Hurley, 2008). One of the well-studied organisms known t o extensively use cilia for movement is the free-living Tetrahymena pyriformis, which belongs to the order Holotrichia, literally meaning cilia all over its membrane. The microorganism is a common fixture in human toxicity studies, because of its cilia’s similarity in terms of morphology and function to that of human epithelial cells (Graf, Graf and Wenz, 1999). Its cell membrane has the characteristic sandwich-like phospholipid bilayer, with the hydrophilic head facing the cytoplasm or the external surroundings, and the hydrophobic chain filling the middle. Given this structure, hydrophilic molecules can more easily pass the membrane, as compared to hydrophobic ones. However, the presence of transport mechanisms allows hydrophobic molecules to enter the cell (Reece, et al., 2011). In cellular permeability studies, an observable cellular change effected by previously identified substance must be utilized in order to clearly determine when and in what conditions the substance penetrated the cell membrane. In this case, the cellular change used was ciliate necrosis and the substance that causes it would be alcohol. This experiment was conducted in order to 1) observe narcosis of T. pyriformis ciliates by alcohol, and 2) discuss the results of ciliate narcosis in terms of membrane permeability. METHOD After preparing propranol and glycerol serial dilutions (propranol: 1.8 M, 1. 5M, 0. 4M, 0. 2M , 0M; glycerol: 2. 8M, 2M, 1. 7M, 1M, 0M) using distilled