HSCI 100 Lecture Notes - Lecture 8: Elastic Fiber, Reticular Fiber, Mast Cell
17 Mar 2016
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Document Summary
Collection of cells of the same type that perform a common function. Cells in tissues are held together by junctions. Tight junction: creates an impermeable junction that prevents the exchange of o materials b/w cells. Found b/w epithelial cells of digestive tract, where they prevent digestive enzymes & microorganism from entering blood. Adhesion junction: holds cells together despite stretching o. Found in tissues that are often stretched (skin, uterus, bladder) Gap junction: allows cells to communicate by allowing small molecules & ions to pass o from cell to cell. Found in epithelia in which the movement of opns coordinates functions [beating of cilia heart/smooth muscle (excitable tissues)] There are >200 diferent types of cells in the human body. There are ~200 trillion cell in the human body. Allows for movement in the body; its contractile". Made of muscle ibers & protein ibers called actin, myosin these 2 interact to produce movement.
