Cytoskeleton Flashcards
actin
Globular protein that links together to form long chains. Microfilaments are composed of two actin filaments twisted together in a helix.
alpha-tubulin
One of two subunits in the molecule tubulin. The other subunit is a similar polypeptide called beta-tubulin. Microtubules are composed of tubulin.
beta-tubulin
One of two subunits in the molecule tubulin. The other subunit is a similar polypeptide called alpha-tubulin. Microtubules are composed of tubulin.
centriole
A component of the centrosome composed of a ring of nine microtubule triplets.
cleavage furrow
The contractile ring of actin microfilaments and myosin that forms during cytokinesis, separating the parent cell into two daughter cells.
cortex
A thin, cross-linked network of actin filaments lying immediately beneath the plasma membrane of animal cells.
cytoplasmic streaming
Flow of cytosol and organelles; involves action of microfilaments.
cytoskeleton
Internal framework of the cell; in eukaryotes, it is composed of microfilaments, intermediate filaments, and microtubules.
depolymerization
Breakdown of a macromolecule through sequential removal of its component subunits.
doublet
An aggregate of two microtubules.
dynamic instability
Instantaneous occurrence of disassembly and assembly on the same site for cytoskeletal components.
dynein
Motor protein associated with microtubules that enables movement of cilia and flagella.
intermediate filament
One of the components of the cytoskeleton; composed of bundles of filamentous proteins. Provides support for cellular structures.
kinesin
Motor protein associated with microtubules that enables movement of organelles and vesicles within the cytoplasm and separation of chromosomes during cell division.
microfilament
A cytoskeletal component composed of two twisted actin filaments; the motor protein myosin enables movement of the microfilaments.
microtubule
A cytoskeletal component made from tubulin. Each microfilament is a hollow rod.
microtubule-organizing center (MTOC)
A structure that facilitates assembly of microtubules.
mitotic spindle
Microtubule array that moves chromosomes during cell division.
motor protein
A type of protein that interacts with microtubules or microfilaments and enables movement.
myosin
Motor protein that is able to pull actin filaments together, resulting in contraction.
nuclear lamina
Interior lining of the nucleus composed of intermediate filaments; maintains the shape of the nucleus and assists in nuclear function.
polymerization
Assembly of a polymer from monomers.
tubulin
Globular protein; dimers of alpha- and beta-tubulin form the hollow rods that compose microtubules
