Phospholipids are amphipathic molecules that have a polar phosphate group at one end and two non polar fatty acids at the other, held together by a glycerol molecule. Look at a phospholipid in your book. Sugars are the building blocks of carbohydrates . Your body maintains the level of the sugar glucose in your blood within a very narrow range. Glucose is the immediate source of energy for your cells.
Sugars occur as ring structures.
In solution, single rings can dynamically change from straight chains to rings and back to straight chains. Notice that every carbon has an oxygen attached to it. One of the disaccharides is common table sugar. Draw its structure below. Background Information 9.