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

(2) 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 (hydrocarbon) 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

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)

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?

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

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

Cis and Trans Fats

Unsaturated but “bad”? Trans Fats