Lipids PACKET 10 CAMPBELLCHAPTER 5 Introduction 2 Contain

Lipids PACKET #10 CAMPBELL—CHAPTER #5

Introduction 2 �Contain carbon, hydrogen and oxygen Does not contain as many oxygen molecules as carbohydrates �Formed via a condensation reaction and broken apart via hydrolysis 1/12/2022 5: 02: 07 AM

Functions of Lipids 3 � Energy � Storage Fats are stored for future energy use � Structural Support Phospholipids � Critical component of the cell membrane � Insulation Especially useful where hair and feathers are of little use � Example Functions of Lipids Energy Storage Structure Insulation Waterproof Underwater • Blubber in whales � Waterproofing Waxes � � Leaf cuticles are made of waxes Secreted from sebaceous glands of the skin 1/12/2022 5: 02: 10 AM

Components of Lipids 4 �Lipids are composed of two parts Glycerol Lipids � Head Hydrophilic Fatty acids Head (Hydrophilic) � Tail Hydrophobic � Some lipids have one of the fatty acids replaced by phosphoric acid These are called phospholipids Tail (Hydrophobic) • Very important component of the cell membrane Glycerol Organic Molecule Fatty Acids Glycerol 1/12/2022 5: 02: 10 AM

Glycerol �A syrupy, sweet, colorless or yellowish liquid, C 3 H 8 O 3, obtained from fats and oils as a byproduct of saponification �Glycerol is used as a solvent, an antifreeze, a plasticizer, a sweetener �Glycerol is used in the production of dynamite, cosmetics, liquid soaps, inks, and lubricants.

Fatty Acid Tails �Chain of carbon and hydrogen joined together.

Fats & Oils

Fats & Oils I �Chemically, fats and oils are triglycerides. Simple lipids Store energy Composed of glycerol and three fatty acid chains. �Triglycerides (at room temperature) Solid � Fats Liquid � Oils

Fats & Oils II 9 � Saturated Fats vs. Unsaturated Fats Saturated � � A molecule that has only single bonds Found largely in animals Unsaturated � � � A molecule that has one or more multiple bonds Largely comes from plants Better for one’s health because the ”kinks” prevent the fat molecules from packing closely together. Helping reduce heart disease 1/12/2022 5: 02: 15 AM

Fats & Oils III—Kinks

Phospholipids

Phospholipids 12 �Found at the surface of cells �Four main components Organic molecule PO 4 {Phosphate/Phosphate Group} � Replaces one of the fatty acid tails Glycerol Fatty acids � Two 1/12/2022 5: 02: 18 AM

Phospholipid Bilayer �Phospholipid bilayer is a series of phospholipids that are found at the surface of cells and helps make up the cell membrane.

Phospholipid Bi-Layer More to come in future packets.

Other Classes of Lipids

Other Classes of Lipids � A number of lipids are not based on the glycerol-fatty acid structure. � However, because they are largely composed of carbon and hydrogen and are non-polar, these molecules are still classified as lipids. Carotenoids � � Cholesterol Cell signals Hormones Vitamins** � Other Classes of Lipids Steroids � Light absorbing pigments Beta carotene Vitamin A is formed from beta carotene in green and yellow vegetables Waxes � Repels water on plants and animals Carotenoids Steroids Vitamins Waxes

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