Cell-Cell Interactions and Communication Flashcards

Flashcards about cell-cell interactions and distant cell communication. Covers cell surfaces, cell-cell attachments and gaps, and distant cell communication.

Fibre Composites

Consists of a cross-linked network of long filaments embedded in a stiff surrounding material called the ground substance.

Extracellular Matrix (ECM)

Provides structural support in animal cells and contains more protein relative to carbohydrate than a cell wall.

Collagen

A cable-like protein that dominates the fibrous component of the animal ECM.

Proteoglycans

Gel-forming proteins that contain the ground substance that surrounds collagen and other fibrous components of the ECM.

Integrins

Membrane proteins that bind to extracellular cross-linking proteins, including laminins.

Primary Cell Wall

A fibre composite secreted by plant cells consisting of long strands of cellulose bundled into microfibrils.

Turgor Pressure

The force exerted by the cell against the wall.

Expansins

Proteins secreted into the cell wall, which disrupt the hydrogen bonds that cross-link the microfibrils in the wall, allowing the microfibrils to slide past one another.

Secondary Cell Wall

An additional layer of material secreted between the plasma membrane and the primary cell wall as plant cells mature.

Lignin

A complex polymer that forms an exceptionally rigid network found in the secondary cell walls of cells that form wood.

Epithelia

Tissues that form external and internal surfaces and serve as barriers between the external and internal environments of plants and animals.

Middle Lamella

A central layer between the walls of adjacent plant cells that consists primarily of gelatinous pectins and serves to glue the cells together.

Tight Junctions

Cell-cell attachments composed of specialized proteins in the plasma membranes of adjacent animal cells that form a watertight seal.

Desmosomes

Cell-cell attachments particularly common in animal epithelial cells and certain muscle cells; they consist of integral membrane attachment proteins that form bridges between anchoring proteins inside adjacent cells.

Antibody

A protein produced by an immune response that binds specifically to a unique type of molecule, often another protein.

Cadherins

Proteins that link cells in desmosomes. Cells from different tissues have different types of cadherins in their plasma membranes.

Gap Junctions

Structures that connect adjacent cells in many animal tissues; specialized proteins assemble in the membranes of adjacent cells, creating interconnected channels that allow water, ions, and small molecules to move between the cells.

Plasmodesmata

Gaps in cell walls that allow direct connections between the cytoplasm of adjacent plant cells; the plasma membrane and cytoplasm of the two cells are continuous.

Symplast

A continuous network of cytoplasm connected by plasmodesmata in plants.

Apoplast

The region outside the plasma membrane in plants, consisting of cell walls, the middle lamella, and air spaces.

Hormones

Information-carrying molecules secreted by plant and animal cells into bodily fluids that act on distant target cells.

Signal Receptor

A protein that changes its shape and activity after binding to a signalling molecule.

Signal Transduction

The conversion of a signal from one form to another.

Second Messenger

Small, nonprotein signalling molecule or ion that elicits an intracellular response to the first messenger.

Protein Kinases

Enzymes that activate or inactivate other proteins by adding a phosphate group to them.

Quorum Sensing

The use of signalling pathways that respond to population density in prokaryotic and eukaryotic microbes.