The Cytoplasm Flashcards
Cytoplasm
the cellular material outside the nucleus but inside the plasma membrane.
The cytoplasm is made of what
half cytosol and half organelles
What does the cytosol consist of
consist of fluid portion, cytoskeleton, and cytoplasmic inclusions
What does the fluid portion consist of
1) solution with dissolved ions and molecules
2) a colloid with suspended molecules especially proteins
the proteins in the fluid portion are mostly what
many of these proteins are enzymes that catalyze breaking down of molecules for energy and synthesis of nucleic acids, amino acid, fatty acids, sugars, and other molecules.
what are the functions of the Cytoskeleton
1) support the cell
2) hold the nucleus and all organelles in place
3) cell movements (such as changes in the cell shape or movement of cell organelles
what does the cytoskeleton consist of
microtubules
actin filaments/microfilaments
intermediate filaments
what are microtubules
are hollow tubules composed primarily of protein
units called tubulin.
what are the functions of microtubules
1) providing support for the cytoplasm
2) supporting cell division (centrioles, spindle fibers)
3) supporting the transport of intracellular materials
4) forming essential components of certain cell organelles, such as cilia and flagella.
what are actin filaments
also called microfilaments small fibrils in the cytoplasm of cells
what are the functions of actin filaments
1) providing structure to the cytoplasm and mechanical support for microvilli,
2) supporting the plasma membrane,
3) defining the shape of the cell.
where are actin filaments found commonly
Muscle cells contain a large number of highly organized actin filaments,
which are responsible for the muscle’s contractile capabilities
Intermediate filaments
protein fibers
function of intermediate filaments
They provide mechanical strength to cells
what do intermediate filaments support give example
intermediate filaments support the extensions of nerve cells,
which have a very small diameter but can be a meter in length.
