2. Regents Biology 2003-2004 Lipids:

3. Regents Biology Lipids Concentrated energy molecules

4. Regents Biology Structure of Fatty Acid Polar End Nonpolar chain

5. Regents Biology 2003-2004 Lipids  Examples  Fats- triglycleride  Oils- triglycerides  Waxes  phospholipids  hormones  sex hormones  testosterone (male)  estrogen (female)

6. Regents Biology 2003-2004 Lipids  Function:  energy storage  very concentrated  twice the energy as carbohydrates!  Animals convert excess carbohydrates into fat  cell membrane  cushions organs  insulates body  think whale blubber!

7. Regents Biology Forming Fat not a chain (polymer) = just a “big fat molecule”

8. Regents Biology Structure of Fat not a chain (polymer) = just a “big fat molecule” 3 fatty acids 1 glycerol Ester link

9. Regents Biology Saturated fats  Most animal fats  solid at room temperature  Limit the amount in your diet  contributes to heart disease  deposits in arteries

10. Regents Biology Unsaturated fats  Plant, vegetable & fish fats  liquid at room temperature  the fat molecules don’t stack tightly together  Better choice in your diet

11. Regents Biology 2003-2004 Saturated vs. unsaturated saturatedunsaturated

12. Regents Biology Hydrogenated Fats  Industrial process  Adds hydrogen atoms to the double bonds in unsaturated triglyceride (liquid fats, ie. Canola oil)  Converts them to semi-solid fats (ie. Margarine or shortening)

13. Regents Biology 2003-2004 Other lipids in biology  Cholesterol  good molecule in cell membranes  make hormones from it  including sex hormones  but too much cholesterol in blood may lead to heart disease

14. Regents Biology 2003-2004 Other lipids in biology  Cell membranes are made out of lipids  phospholipids  heads are on the outside touching water  “like” water  tails are on inside away from water  “scared” of water  forms a barrier between the cell & the outside