Cell Communication Vocab Words Flashcards
channel protein
A type of transport protein that functions by having a hydrophilic channel that certain molecules or atomic ions use as a tunnel through a membrane.
ion channel
A transmembrane protein channel that allows a specific ion to diffuse across the membrane down its concentration or electrochemical gradient.
gated channel
A transmembrane protein channel that opens or closes in response to a particular stimulus.
membrane potential
The difference in electrical charge (voltage) across a cell’s plasma membrane due to the differential distribution of ions. Affects the activity of excitable cells and the transmembrane movement of all charged substances.
local regulator
A secreted molecule that influences cells near where it is secreted.
growth factor
A class of local regulators that stimulate nearby target cells to grow and divide.
paracrine signaling
A type of local signaling in animals in which a secreting cell acts on nearby cells by discharging a local regulator such as a growth factor.
synaptic signaling
A type of local signaling in animals in which an electrical signal stimulates release of a neurotransmitter molecule into a synapse, stimulating the target cell on the other side of the synapse.
hormone
In multicellular organisms, one of many types of secreted chemicals that are formed in specialized cells, travel in body fluids, and act on specific target cells in other parts of the body, changing the target cells’ functioning. Important in long-distance signaling.
endocrine signaling
A type of long-distance signaling in animals that utilizes hormones.
reception
The binding of a signaling molecule to a receptor protein, activating the receptor by causing it to change shape.
transduction
The conversion of a signal from outside the cell to a form that can bring about a specific cellular response.
signal transduction pathway
A series of steps linking a mechanical, chemical, or electrical stimulus to a specific cellular response.
response
The change in a specific cellular activity brought about by a transduced signal from outside the cell.
ligand
A molecule that binds specifically to another molecule, usually a larger one.
G protein-coupled receptor
A signal receptor protein in the plasma membrane that responds to the binding of a signaling molecule by activating a G protein.
G protein
A GTP-binding protein that relays signals from a plasma membrane signal receptor, known as a G protein-coupled receptor, to other signal transduction proteins inside the cell.
ligand-gated ion channel
A transmembrane protein containing a pore that opens or closes as it changes shape in response to a signaling molecule (ligand), allowing or blocking the flow of specific ions; also called an ionotropic receptor.
transcription factor
A protein that controls which genes are turned on.
protein kinase
An enzyme that transfers phosphate groups from ATP to a protein, thus phosphorylating the protein.
protein phosphatase
An enzyme that removes phosphate groups from (dephosphorylates) proteins, often functioning to reverse the effect of a protein kinase.
second messenger
A small, nonprotein, water-soluble molecule or ion, such as a calcium ion (Ca2+) or cyclic AMP, that relays a signal to a cell’s interior in response to a signaling molecule bound by a signal receptor protein.
cyclic AMP
Cyclic adenosine monophosphate, a ring-shaped molecule made from ATP that is a common intracellular signaling molecule (secondary messenger) in eukaryotic cells. It is also a regulator of some bacterial operons.
phosphorylation cascade
A series of chemical reactions during cell signaling mediated by enzymes (kinases), in which each kinase in turn phosphorylates and activates another, ultimately leading to phosphorylation of many proteins.
