Cytoskeleton Essay

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Cytoskeleton The cytoskeleton is a network of fibers throughout the cell's cytoplasm. This structure acts as both muscle and skeleton, for movement, stability and cell’s shape maintain. It is not an organelle. The cytoskeleton is composed of protein filaments and is found throughout the inside of a eukaryotic cell. Plays a major role in locomotion, chromosome separation in mitosis and meiosis and intracellular transport of organelles. The cytoskeleton is made up of three kinds of protein filaments: [pic] • Actin filaments (also called microfilaments) They are about 8 nm in diameter, and are thinnest of all cytoskeletal filaments. They are mede up of actin. Actin filaments provides mechanical strength to the cell, links transmembrane proteins (Protein that passes one or more times through the lipid bilayer of a cell membrane) to cytoplasmic proteins. Most actin molecules work together to give support and structure to the plasma membrane and are therefore found near the cell membrane. Can generate locomotion in cells such as white blood cells and the amoeba, to provide phagocytosis. interact with myosin ("thick") filaments in skeletal muscle fibers to provide the force of muscular contraction. [pic] [pic] ● Intermediate Filaments These cytoplasmic fibers average 10 nm in diameter (and thus are "intermediate" in size between actin filaments (8 nm) and microtubules (25 nm). Intermediate filaments play similar roles in the cell: providing a supporting framework within the cell. Provide support for microfilaments and microtubules by holding them in place. There are several types of intermediate filament, each constructed from one or more proteins characteristic of it. • keratins are found in epithelial cells and also form hair and nails; • nuclear lamins form a meshwork that stabilizes the inner membrane of the
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