With this new concept in your students minds. you can now begin discussing how cells can utilize dehydration synthesis and hydrolysis reacfions to build macromolecules consisting of thousands of smaller molecules. These macromolecules will play important roles in the cell's metabolic functions. The first group of macromolecules to be discussed with your students is the lipids. Lipids are characterized by long chains of carbons and hydrogen atoms linked by nonpolar bonds. These tydrocasbon chains are nonpolar, hydrophobic (hydro-meaning "water" and phobic meaning "afraid of") macromolecules, which is the causal fretor responsible' for many of the important functional characteristics of lipids. These long chains can be differentiated frort one another by the numbet of carbons present, the degree of saturation (every carbon atoms in the fatty acid chain has two hydrogen atoms bound to it), and the terminal carboxyl group. Which is used to dassily liplds into different classes of fatty acids. Triglycerides and phospholipids are two types of lipids with similar configurations and important blological roles. Triglycnides are formed by a series of dehydration feactions that join three fatty acid chains to a three-carbon molecule of plycerol. Alternatively, a phospholipid is formed when a glycerol molecule is bound to two fatty acid chains and a phosphate group. Since triglycendos and phospholipidn are similar in construction and structure, they also share many functional properties, In both molecules, the glycerol head" is hydrophilic and the fatty acid "talls" are hydrophobic, which gives the macromolecule an amphipathe nature.-that is. the oresence of onootina properties within one molecule. Using the following terms; correctly label the figures below. roCareers: Teaching the Building Blocks