Chapter 17 Cell Biology

Front 1

actin filament

Back 1

protein filament about 7 nm wide formed from a chain of globular acim molecules. A mjor costituent of cytoskeleton. Abundant in muscle cells

Front 2

cell cortex

Back 2

specialized layer of cytoplasm on the inner face of the plasma membrane. In animal cells it is an actin rich layer responsible for cell surface movements

Front 3

centriole

Back 3

short cylindrical array of microtubules, usually found in pairs at the center of centrosomes in animal cells. Also found at the base of cilia and flagella.

Front 4

centrosome

Back 4

centrally located organelle of animal cells that is the primary microtubule organizing center and acts as the spindle pole during mitosis. In most animal cells it contains a pair of centrioles.

Front 5

cilium

Back 5

hairlike extension on the surface of a cell with a core bundles of mt and capable of performing repeated beating movmt of fluid over epithelial cells

Front 6

cytoskeleton

Back 6

system of protein filaments in the cytoplasm of a cell that gives the cell shape and the capacity for directed mvmt.

Front 7

dynamic instability

Back 7

the property shown by mt of growing and shrinking repeatedly through the addition oand loss of tubulin subunits from their exposed ends.

Front 8

dynein

Back 8

member of a family of large motor proteins that undergo ATP dependent movement along microtubules. Dynein is responsible for the bending of cilia.

Front 9

filopodium

Back 9

long thin actin containing extension on teh surface of an animal cell. sometimes has an exploratory function, as in a growth cone.

Front 10

flagellum

Back 10

long, whiplike protrusion tha tdrives a cell through a fluid medium by its beating. Eucaryotic flagella are longer versions of cilia; bacteria are different and simpler.

Front 11

intermediate filament

Back 11

fibrous protein filament that forms ropelike networks in animal cells often used as a structural element that resists tension applied to teh cell from outside.

Front 12

kinesin

Back 12

one member of a large family of motor protein that uses the entergy of ATP hydrolysis to move along a microtubule.

Front 13

lamellipodium

Back 13

dynamic sheetlike extension on the surface of an animal cell, especially one migrating over a surface.

Front 14

microtubule

Back 14

long, stiff cylindrical structure, composed of the protein tubulin. Used by eucaryotic cells to regulate their shape and control their mvmt.

Front 15

motor protein

Back 15

protein such as myosin or kinesin that uses energy derived from ATP hydrolysis to propel itself along a protein filament or polymeric molecule.

Front 16

myosin

Back 16

type of motor protein that uses ATP to drive movements along actin. Forms the thick filaments of skeletal muscle. responsible for many actin based movements.

Front 17

nuclear lamina

Back 17

fibrous layer on the inner surface of the inner nuclar membrane made up of a network of intermediate filaments made from nuclear lamins.

Front 18

polarity

Back 18

refers to a structure such as an actin filament or a fertilized egg that hasa n inherent direction so that one can distinguish one end from the other.

Front 19

Rho protein family

Back 19

Family of monomeric GTPases involved in signaling the rearangement of the actin cytoskeleton

Front 20

sarcomere

Back 20

repeating unit of a myofibril in a muscle cell, about 2.5 micrometer long composed of an array of overlapping thick and thin filaments.

Front 21

tubulin

Back 21

protein from which microtubules are made.