Chapter 17 Key Terms Flashcards
Protein that interacts with actin monomers or filaments to control the assembly, structure, and behavior of actin filaments and networks.
Actin-binding protein
Thin, flexible protein filament made from a chain of globular actin molecules; a major constituent of all eukaryotic cells, this cytoskeletal element is essential for cell movement and for the contraction of muscle cells.
Actin filament
Specialized layer of cytoplasm on the inner face of the plasma membrane. In animal cells, it is rich in the actin filaments that govern cell shape and drive cell movement.
Cell cortex
Cylindrical array of microtubules usually found in pairs at the center of a centrosome in animal cells. Also found at the base of cilia and flagella, where they are called basal bodies,
Centriole
Hairlike structure made of microtubules found on the surface of many eukaryotic cells; when present in large numbers, its rhythmic beating can drive the movement of fluid over the cell surface, as in the epithelium of the lungs.
Cilium (plural cilia)
System of protein filaments in the cytoplasm of a eukaryotic cell that gives the cell shape and the capacity for directed movement. Its most abundant components are actin filaments, microtubules, and intermediate filaments.
Cytoskeleton
The rapid switching between growth and shrinkage shown by microtubules.
Dynamic instability
Motor protein that uses the energy of ATP hydrolysis to move toward the minus end of a microtubule. One form of the protein is responsible for the bending of cilia.
Dynein
Long, thin, actin-containing extension on the surface of an animal cell. Sometimes has an exploratory function, as in a growth cone.
Filopodium (plural filopodia)
Long, whip-like structure capable of propelling a cell through a fluid medium with its rhythmic beating. Eukaryotic ________ are longer versions of cilia; bacterial _______ are completely different, being smaller and simpler in construction.
Flagella (plural flagellum)
Fibrous cytoskeletal element, about 10 nm in diameter, that forms rope-like networks in animal cells; helps cells resist tension applied from outside.
Intermediate filaments
Class of intermediate filament abundant in epithelial cells, where it provides tensile strength; main structural component of hair, feathers, and claws.
Keratin filament
A large family of motor proteins that uses the energy of ATP hydrolysis to move toward the plus end of a microtubule.
Kinesin
Dynamic sheetlike extension on the surface of an animal cell, especially one migrating over a surface.
Lamellipodium (plural lamellipodia)
Long, stiff, hollow, cylindrical structure composed of the protein tubulin. Used by eukaryotic cells to organize their cytoplasm and guide the intracellular transport of macromolecules and organelles.
Microtubule
