Carbohydrates & Lipids Chapter 3 Biochemistry
What you need to know! The role of dehydration synthesis in the formation of carbohydrates. How to recognize the difference between the 4 biologically important organic compounds by their structure formulas The cellular functions of carbohydrates & lipids
Carbohydrates Contain only C, H, O Formula (CH2O)n “n” indicates the number of carbons Primarily energy molecules (some are structural) All carbs are generally hydrophilic
Monosaccharides Monomers for polysaccharides or independent sugars Hexose sugars have 6 carbons and are hexagonal or pentagonal Primarily provides energy Single sugars joined together by condensation Form glycosidic bonds
Disaccharides Two simple sugars joined together (dimer) Sucrose (table sugar) = 1 glucose + 1 fructose Maltose (malt sugar) = 1 glucose + 1 glucose Primarily energy molecules
Polysaccharides Energy storage Amylose (starch in plants) Glycogen (liver in animals) Structural Polysaccharides Cellulose (plants) Chitin (fungi, insects) Starch, glycogen, cellulose, chitin are all made out of glucose molecules They differ in their glycosidic bonds
Cellulose = Fiber *Cellulose 1-4 B glycosidic bonds *“O” up – “O down rotation Indigestible to animals Only bacteria can hydrolyze the glycosidic bonds of cellulose
Lipids/Fats: Contain C, H, O, P Contain lots of H Made of (no true monomer): glycerol and fatty acids Lipids are individual macromolecules not polymers Extremely diverse category All are hydrophobic
Fatty Acids Saturated fatty acid = very stable Solid at room temperature (RT) butter, lard Single bonds Unsaturated fatty acid = less stable Liquid at RT Olive oil, canola oil, nut based oils
Lipids Long term energy storage: Triglycerides Adipose Tissue (animals) Seeds (plants) Cell membrane Phospholipids = 1 glycerol, 1 phosphate, and 2 fatty acids
Lipids Steroid hormones Protective waxes (leaf, ear) Ring structure with one fatty acid estrogen, testosterone, progesterone, cortisol Cholesterol: maintains cell membrane fluidity Protective waxes (leaf, ear) Waterproofing, and keeps out unwanted organisms