Gene DNA RNA Protein Amino acid Nucleic acids Nucleic Acids ● Include DNA and RNA Information storage molecules They provide the directions for building proteins

Phosphate group Nitrogenous base  A, G, C, or U  Uracil  U  Sugar  ribose  Nitrogenous base (A,G,C, or T) Phosphate group Thymine (T) Sugar (deoxyribose) Phosphate Base Sugar ●Nucleic acids are polymers of nucleotides –DNA, deoxyribonucleic acid –RNA, ribonucleic acid Nucleic Acids

●Each nucleotide has one of the following bases:

Nucleic Acids Sugar-phosphate backbone Nucleotide Base pair Hydrogen bond Bases  a  DNA strand  polynucleotide   b  Double helix  two polynucleotide strands  ●Nucleic Acid Structure

Nucleic Acids ●Nucleic Acid Structure

DNA Structure Nucleic Acids

Carbohydrates include Carbohydrates –Small sugar molecules in soft drinks Monosaccharides & Disaccharides –Long starch molecules in pasta and potatoes Polysaccharides

Monosaccharides are simple sugars Monosaccharides –Glucose, found in sports drinks –Fructose, found in fruit Honey contains both glucose and fructose Glucose Fructose Isomers

In aqueous solutions, monosaccharides form rings (b) Abbreviated ring structure Monosaccharides

A disaccharide is a double sugar Disaccharides Disaccharides are joined by the process of dehydration synthesis Glucose Maltose

The most common disaccharide is sucrose, common table sugar –It consists of a glucose linked to a fructose –Sucrose is extracted from sugar cane and the roots of sugar beets Disaccharides

Polysaccharides (a) Starch Starch granules in potato tuber cells Glucose monomer (b) Glycogen Glycogen Granules In muscle tissue (c) Cellulose Cellulose molecules Cellulose fibril in a plant cell wall –They are long chains of sugar units –They are polymers of monosaccharides

●Lipids are: Neither macromolecules nor polymers Hydrophobic, unable to mix with water Lipids Oil (hydrophobic) Vinegar (hydrophilic) Figure 3.10

●FATS ● Dietary fat consists largely of the molecule triglyceride Lipids –A combination of glycerol and three fatty acids Fatty acid Glycerol (a) A dehydration reaction linking a fatty acid to glycerol (b) A fat molecule with a glycerol “head” and three energy-rich hydrocarbon fatty acid “tails”

●Unsaturated fatty acids Lipids (Fats) –Have less than the maximum number of hydrogens bonded to the carbons ●Saturated fatty acids –Have the maximum number of hydrogens bonded to the carbons

Lipids (Fats) Saturated Fats TYPES OF FATS Unsaturated Fats Margarine Plant oils Trans fats Omega-3 fats INGREDIENTS: SOYBEAN OIL, FULLY HYDROGENATED COTTONSEED OIL, PARTIALLY HYDROGENATED COTTONSEED OIL AND SOYBEAN OILS, MONO AND DIGLYCERIDES, TBHO AND CITRIC ACID ANTIOXIDANTS

Phospholipids Steroids Lipids

Cholesterol TestosteroneA type of estrogen ●STEROIDS Steroids are very different from fats in structure and function. Lipids

Visual Summary 3.2 Biological Molecules