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.
Protein macromolecules basically build all cells and make them work. Enzymes are also proteins. Without protein, you'd be very unhealthy and you wouldn't have any new cells and they wouldn't function quite so well!   A macromolecule is a molecule made up of two or more smaller molecules.   A very large molecule such as a polymer or protein, consisting of many smaller struct â¦ ural units linked together. 30 people found this useful. Judy Olmsted. 78,531 Contributions. Retired college science professor.