BIOLOGY 2B03 Lecture Notes - Lecture 17: Tight Junction, Claudin, Cadherin
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Document Summary
In an experiment two different sponge cells were mixed together and they were able to separate and reform themselves. In another experiment two different germ layers from two different samples of the same species were mixed together, and the formed an embryo. Linear arrays of proteins called occuldin and claudin are closely arranged between neighboring cells. Freeze fracturing, a process in which cells are instantly frozen in liquid nitrogen and then broken apart, can be used to view this array of proteins s and en en. In this picture you can see that the tight junction doesn"t allow certain molecules to diffuse, such as the injected lanthanum hydroxide. They directly link the cytosol of neighboring cells. This integrates the metabolic activities of all the cells in a tissue, by allowing the exchanges of ions and small molecules between each other (such as calcium and cam.