Cells have proteins called receptors that bind to signaling molecules and initiate a physiological response. Different receptors are specific for different molecules. Dopamine receptors bind dopamine, insulin receptors bind insulin, nerve growth factor receptors bind nerve growth factor, and so on.hosphate groups can be added to multiple sites in a single protein, and a single protein may in turn be the substrate for multiple kinases and phosphatases. At any one time, a cell is receiving and responding to numerous signals, and multiple signal transduction pathways are operating in its cytoplasm.
Definition of macropore. : a pore (as in coal) of comparatively large size; especially : a pore in soil of such size that water drains from it by gravity and is not held by capillary action.
A macromolecule is a very large molecule, such as protein, commonly created by the polymerization of smaller subunits. They are typically composed of thousands of atoms or more. The most common macromolecules in biochemistry are biopolymers and large non-polymeric molecules. Synthetic macromolecules include common plastics and synthetic fibers as well as experimental materials such as carbon nanotubes.