A very abundant protein in eukaryotic cells that is the main component of
Approximately 5-9 nanometers in diameter. Provide structural support to the
plasma membrane. As a cytoskeletal protein provides for movement of
organelles within cells.
A round structure that holds together sister chromatids.
A region of the cell near the nucleus from which microtubules sprout.
are not found in all cells. Centrosomes are comprised of two centrioles.
A structure composed of DNA and proteins containing all the genetic material of
a cell. Found in the cell nucleus.
A fluid found in the main compartment of eukaryotic cells. Includes
everything outside the cell nucleus but the organelles and the
cytoskeleton. The main component is cytosol.
A system of protein filaments found throughout the cytoplasm of eukaryotic
cells that help provide for cell structure. Composed of actin,
intermediate filaments, and microtubules.
The main component of the cytoplasm that fills the main compartment of
A membrane-bound organelle found in eukaryotic cells. Makes direct contact
with the cell nucleus and, since it is dotted with ribosomes, is the site of
lipid and protein synthesis. Comes in two
forms, smooth and rough.
A membrane-bound organelle found in eukaryotic cells. Responsible for
delivering molecules to the lysosome for digestion.
An organism composed of one or more cells with defined intracellular components
including a nucleus and cytosol. Includes all organisms except
A membrane-bound organelle found near the cell nucleus in eukaryotic cells.
Responsible for sorting and packaging proteins for secretion to various
destinations in the cell.
One of three protein components of the cytoskeleton. A fibrous protein
filament approximately 10 nanometers in diameter. Forms the nuclear lamina that
helps protect the cell nucleus.
The space between the outer and inner membrane in a mitochondria.
A membrane-bound organelle found in eukaryotic cells. Contain acids and
enzymes that degrade unwanted molecules.
The space inside the inner membrane of mitochondria.
One of three protein components of the cytoskeleton. Long, cylindrical
structures approximately 25 nanometers in diameter. Extend from the centrosome
to all parts of the cell, forming tracks on which organelles can travel
within the cell. Microtubules can be either kinetocore microtubules or
non-kinetocore microtubules. Kinetocore microtubules bind to sister
mitosis; non-kinetocore microtubules do not.
An organelle within the cell. Much of cell
respiration is carried out within
A large, double membrane-bound organelle found in eukaryotic cells.
Contains DNA and RNA.
A membrane-bound sub-cellular structure found in eukaryotic cells. The Cell
nucleus, mitochondria, ER, and golgi apparatus are all examples.
A small, membrane-bound organelle found in eukaryotic cells. Contains
oxidizing enzymes that oxidize organic molecules and process hydrogen peroxide
in the cell.
An organism composed of usually one, but occasionally more, cells that lack
defined sub-cellular compartments. All essential material is enclosed within
the cell membrane. Includes all bacteria and
A molecule composed of ribosomal RNA*
proteins, and located on the endoplasmic reticulum**. Responsible for
Rough endoplasmic reticulum
Endoplasmic reticulum that is coated with ribosomes and involved in
Smooth endoplasmic reticulum
Naked endoplasmic reticulum that lacks ribosomes and is more involved in