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.
CH 5. Structure & Function of Large Molecules: Macromolecules. Molecules of Life. All living things are made up of four classes of large biological molecules: carbohydrates, lipids, proteins, and nucleic acids. Macromolecules are large molecules composed of thousands of covalently connected atoms. Molecular structure and function are inseparable. Macromolecules: Polymers built from Monomers A polymer is a long molecule consisting of many similar building blocks. These small building-block molecules are called monomers. Three of the four classes of lifeâs organic molecules are polymers: Carbohydrates Proteins Nucleic acids Synthesis & Breakdown of Polymers A dehydration reaction occurs when two monomers bond together through the loss of a water molecule.