7.2 Proteins in the cell and on its surface receive signals from other cells. â¢ There are usually several amplifying steps betweenthe binding of a signal molecule to a cell surfacereceptor and the response of the cell.ecause these proteins may constituteless than 0.01% of the total mass of protein in a cell, puri-fying them is analogous to searching for a particular grainof sand in a sand dune! However, two recent techniqueshave enabled cell biologists to make rapid progress in thisarea. 7.1 Cells signal one another with chemicals.
A macromolecule is a very large molecule commonly created by polymerization of smaller subunits (monomers). They are typically composed of thousands or more atoms.
A molecule containing a very large number of atoms, such as a protein, nucleic acid, or synthetic polymer. Example sentences. 1  During these reactions, they are chemically linked forming macromolecules, or polymers, which have large molecular weights. molecule containing a very large number of atoms, such as a protein, nucleic acid, or synthetic polymer. Example sentences. 1  During these reactions, they are chemically linked forming macromolecules, or polymers, which have large molecular weights.