Microfilaments Filaments Fiber About 25 nm 8 to 11 nm Around 7 nm Diameter One of different Tubulin, with types of Protein two subunits, proteins such Actin Composition alpha and as lamin, beta tubulin vimentin, and keratin Hollow cylinders Protein fiber Two actin made of two coils twisted chains twisted protein chains into each around one twisted other another around each other Organize cell position Keep cellular organelles in shape; allow Organelle and cytoplasm; movement of vesicle provide certain cells by movement; structural forming form mitotic support of cytoplasmatic Main spindles the nuclear extensions or Functions during cell envelope and contraction of reproduction; sarcomeres; actin fibers; cell motility involved in involved in (in and cell-to-cell some flagella) and or matrix matrix junctions junctions Keratin Actin Molecular intermediate cytoskeleton of structure of filaments in mouse embryo microtubules. skin cells cells. (stained red). The cytoskeleton is discussed in the following video: (4:50). Go to for more content Summary The cytoplasm consists of everything inside the plasma membrane of the cell.
Filaments Microfilaments Fiber Diameter About 25 nm 8 to 11 nm Around 7 nm Protein Composition Tubulin, with two subunits, alpha and beta tubulin One of different types of proteins such as lamin, vimentin, and keratin Actin Hollow cylinders made of two protein chains twisted around each other Protein fiber coils twisted into each other Two actin chains twisted around one another Main Functions Organelle and vesicle movement; form mitotic spindles during cell reproduction; cell motility (in and flagella) Organize cell position organelles in cytoplasm; provide structural support of the nuclear envelope and sarcomeres; involved in cell-to-cell and junctions Keep cellular shape; allow movement of certain cells by forming cytoplasmatic extensions or contraction of actin fibers; involved in some or junctions Molecular structure of microtubules. Keratin intermediate filaments in skin cells (stained red). Actin cytoskeleton of mouse embryo cells. The cytoskeleton is discussed in the following video: (4:50). Go to for more content Summary The cytoplasm consists of everything inside the plasma membrane of the cell. matrix matrix
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