Cell Growth and Differentiation


cell differentiation

process by which a cell changes to become specialized to perform a certain function

cell wall

rigid carbohydrate structure that provides overall support and protection for the cell. It is found in some, but not all, cells.

cellulose microfibril

bundle of polysaccharide chains that contributes to plant cell wall structure


protein that makes up the bulk of the extracellular matrix in animal tissues


cell junction that connects cells via specialized proteins and helps maintain tissue strength

embryonic stem cell (ES cell)

undifferentiated cell that can give rise to more differentiated cells in a developing animal embryo

epithelium (plural, epithelia)

tissue made of a sheet of cells that covers the surface of the body as well as the outside and inside of many internal organs

extracellular matrix

molecular framework secreted by cells that supports them structurally and biochemically


cell that makes the extracellular matrix, including collagen


extracellular protein that attaches cell membrane proteins to collagen

gap junction

structure that connects adjacent cells via protein channels, allowing the direct movement of small molecules and ions from the cytoplasm of one cell to the cytoplasm of the next cell

glycosaminoglycan (GAG)

polysaccharide chain of repeating disaccharides, usually linked to a core protein, that forms part of the extracellular matrix


junction complex that binds epithelial cells to the basal lamina (border between epithelium and connective tissue)

induced pluripotent stem cell (iPS)

adult cell that has been transformed into a pluripotent stem cell (able to give rise to any other body cell type) through the application of specific stimuli

inner cell mass

collection of stem cells in an early embryo that will give rise to the different parts of the developed animal

multipotent stem cell

stem cell that can give rise to a limited number of other body cell types

plasmodesma (plural, plasmodesmata)

small channel connecting the cytoplasm of adjacent plant cells through which molecules pass

pluripotent stem cell

stem cell that can give rise to many different cell types

reproductive cloning

formation of an animal that is a genetic copy of its genetic donor by transplanting the nucleus of a somatic cell into an egg that has had its nucleus removed

therapeutic cloning

transfer of the nucleus of a somatic cell into an egg cell that has had its nucleus removed to form an embryo, from which embryonic stem cells can be derived

tight junction

protein junction that connects the plasma membranes of two cells, preventing molecules from passing through the space between cells


integrated, cooperative assembly of cells working together

totipotent stem cell

stem cell that is able to give rise to an entire organism from a single cell