Macromolecules Lipids

Common myths and misconceptions…do you have something to learn?  /19279/ cw/index.html /19279/ cw/index.html

Lipids Are…  Macronutrients  ??  Organic molecules  ??  Essential nutrients  ??

1. What elements are always in fats/lipids?  C, H, O

Intro to Lipids  There are three types of lipids  Triglycerides  These are the lipids commonly known as fat  Phospholipids  Sterols

2. What is the basic structure?  Triglycerides & Phospholipids:  Fatty acids: long chains of C and H with an acid group “COOH” at the end  There are 20 different fatty acids that make up these lipids  Essential vs. non essential  Sterols – fused ring structure

3. What two "parts" or "portions" are there in the general structure of fats?  The TRI glycer ide, commonly known as fat, is made up a THREE fatty acids connected to one glycerol

4. What is a general property of all lipids?  Hydrophobic  “Hydro” = water  “Phobic” = fear  In other words, they DO NOT dissolve in water

5. What is the difference between the structure of saturated and unsaturated fats?

Fatty Acids  They vary by : 1.Length of chain 2.Whether the carbons have a SINGLE OR DOUBLE bond between them (saturated or unsaturated) 3.Total number of double bonds (monounsaturated or polyunsaturated)

Unsaturated vs. Saturated Fatty Acids  Unsaturated fatty acids: a fatty acid with one or more double bonds between carbons  Saturated fatty acids: a fatty acid with all of its carbons bound to a hydrogen  NO DOUBLE BONDS

Monounsaturated vs. Polyunsaturated Fatty Acids  Monounsaturated: ONE double bond between carbons  Polyunsaturated: Two or more (many) double bonds between carbons

Cis and Trans Fats

Unsaturated but “bad”? Cis and Trans Fats

6. What is the difference between what unsaturated and saturated fats look like at room temperature?  Saturated fats tend to be solid at room temperature  Unsaturated fats tend to be liquid at room temperature

7. What are some general functions of fats/lipids in the body? 1. Energy storage  Your body has an UNLIMITED ability to store excess calories as fat  Your fat reserves have the ability to enlarge as much as 1000X their original size 2. Insulation & maintenance of body temperature 3. Transport proteins in blood 4. Allows you to absorb certain vitamins

8. Identify at least TWO specific examples of fats/lipids and explain their functions in the body.  Phospholipid:  Make up the membrane of your cells  Cholesterol:  Part of your cells’ membrane; provides structure  Cholesterol is needed to make vitamin D, sex hormones, and bile acids

9. What are some food sources of saturated fat?  Animal sources such as meat  Whole-milk dairy products (butter, ice cream, cheese)  Candies  Commercially made baked goods

10. What are some food sources of unsaturated fat?  Corn, canola, and soybean oils  And products made with them  Almonds, peanuts, walnuts  Fish: salmon, herring, sardines  Seafood: lobster, shrimp

Nutrition Sleuth – Assessing the Fat Content of Fast Foods  /19279/ cw/index.html /19279/ cw/index.html