DO NOW! 1. What is the molecular formula for glucose? C 6 H 12 O 6 2. Which of the following is made up of simple sugars: a candy bar or a serving of pasta? candy bar 3. Which do you think will give you energy quicker? candy bar 4. Does this energy last long? Explain… No!

Lipids Lipids include fats, oils, and waxes. 1.Chemical Composition  Lipids consist mainly of carbon and hydrogen, held together by covalent bonds.  Lipids (fats) are formed from the combination of three fatty acids and a glycerol molecule through a process known as dehydration synthesis. This is also known as a condensation reaction.

Draw and label the following lipid (triglyceride) in your notes: 2.Functions of Lipids  Reserve energy supply: lipids can supply about twice as much energy as the same amount of carbohydrate.  Lipids make up cell structures, especially the cell membrane.  Mammals store fats under the skin to cushion and protect the body as well as insulate against heat loss.

3.Saturated and Unsaturated Fats  Saturated fats are made with fatty acids that contain only single bonds between the carbon atoms (C—C).  Unsaturated fats have one or more pairs of carbon atoms in the fatty acid molecule that are joined by a double (C=C) or triple bond.  Cholesterol is a necessary compound found in animals that can cause heart problems when in excess. A diet high in saturated fats is associated with high cholesterol levels in humans.

Check Your Understanding 1. READ pages “Lipids” 2. Describe how the three major types of lipids – triglycerides, phospholipids, and waxes, differ in structure from one another. 3. Give examples of saturated fats and unsaturated fats. Which type is healthier to include in your diet? 4. Why do phospholipids arrange in a bilayer when in a watery environment such as a cell?