• Motor protein that makes up the microfilament

• interaction of cytoskeleton with motor proteins and plasma membrane help cell move along fibers outside cell.
• motor proteins that attach to receptors on vesicles can "walk" the vesicles along microtubules or microfilaments

• cilia
  • occurs in large numbers in each cell
  • beating pattern
    • work like oars, with alternating power and recovery strokes generating force in a direction perpendicular to the ciliums axis.

• a network of fibers extending through the cytoplasm
• made up of 3 types of molecular structures
  • microtubules- thickest
  • microfilaments- thinnest
  • intermediate filaments- middle
• gives cell mechanical support and shape
• stabalized by a balance between opposing forces exerted by it's elements
• anchorage for many organelles and cytosolic enzyme molecules
• can be dismantled and reassembled
• manipulates the plasma membrane in a way that forms food vacuoles or other photogocytic vesicles
• transmit forces exerted by extracellular molecules via cell surface proteins
• center for cell motility

both

• a core of micrtubules sheathed n an extension of the plasma membrane
• 9+2 pattern
  • 9 doublets of microtubules
  • each pair sharing part of their walls
  • in a ring
  • 2 single tubules in the middle
• 9+0 pattern
  • non motile because the dont have microtubules in the middle
  • anchored by basal body similar to centriole
• felxible cross-linking proteins, evenly spaced along the length of cilium or flagellum, connect the outer doublets to each other and to 2 central microtubules
• outer doublet has piors of protruding proteins, called dynein, spaced along its length and reach neighbor doublet
• energy provided by ATP
• unrestrained by cross-linking
  • dynien bending resembles walking
  • if a doublet passes the other it just looks longer
• cross-linking protein
  • cannot slide past eachother very fast and so they bend
  • the protein holds them back

• Large motor protein
• each composed of polypeptides
• help organelle bend
• crosslinking proteins
  • spaced along outer doublet stretched along it's length that reach neighbor doublet

• singular flagellum
• microtubule- containing extensions that project from some cells
• occurs in small numbers
• beating pattern
  • udulating motion that generates force in same direction as the flagellums axis

• Specialized for braring tension
• consistent in diameter and composition in a all eukaryotic cells 8-12nm
• made of severak different proteins of the keratin family depending on cell type
• permanent fixtures always retains original shape
• important in reinforcing the shape of cell and anchoring the position of certain organelles and nucleus
• formation of nuclear lamina

• 7 nm
• built from actin protein
• twisted double chain of actin subunits
• may form structural networks
• present in all eukaryotic cells
• functions:
  • to bear tension
  • changes in cell shape
  • muscle contraction
  • cytoplasmic streaming
  • cell motility (as in pseudopia)
  • cell division (cleavage furrow formation)
• 3 dimensional network of microfilaments inside plasma membrane helps support the cells shape

• Hollow tubes; wall consist of 13 columns of tubulin molecules
• 25nm with 15nm lumen
• made of tubulin, a dimer consisting of alpha-tubulin and beta-tubulin
• functions
  • maintenance of cell shape (compression-resisting girders)
  • cell motility (cilia or flagella)
  • chromosome movements in cell division
  • organelle movements

• interact with cytoskeleton during cell motility
• bring about the bending of cilia and flagella by gripping microtubules within those organelles and sliding them against each other

• protein that makes up microtubules
• made up of alpha tubulin and beta tubulin dimers