4 CLASSES OF MACROMOLECULES Carbohydrates (sugars) Lipids (fats) Nucleic Acids Proteins

Fig. 5-UN2

Fig. 5-UN2a

Fig. 5-UN2b

Figure 5.2 The synthesis and breakdown of polymers

Uses of Sugars in Cells Fuel – Energy source e.g. Combustion of glucose during cellular respiration Source of carbon (Building blocks) for molecules such as DNA

Carbohydrate Memorize List Monosaccarides – glucose, galactose, fructose Disaccharides – maltose, lactose, sucrose Polysacharides – starch, glycogen and cellulose

Figure 5.3 The structure and classification of some monosaccharides

Figure 5.5 Examples of disaccharide synthesis

Figure 5.7b,c Starch and cellulose structures

(b) Glycogen: an animal polysaccharide Fig. 5-6 ENERGY STORAGE MOLECULES Chloroplast Starch Mitochondria Glycogen granules 0.5 µm 1 µm Amylose Glycogen Amylopectin (a) Starch: a plant polysaccharide (b) Glycogen: an animal polysaccharide PLANTS ANIMALS

Figure 5.29 The components of nucleic acids

Figure 16.5 The double helix

CHAPTER 5 THE STRUCTURE AND FUNCTION OF MACROMOLECULES Section C: Lipids - Diverse Hydrophobic Molecules 1. Fats store large amounts of energy 2. Phospholipids are major components of cell membranes 3. Steroids include cholesterol and certain hormones Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Properties of Lipids Lipids are NOT POLYMERS Lipids are HIGHLY DIVERSE in STRUCTURE and FUNCTION HYDROPHOBIC- Lipids have little or no affinity for water

FAT IS USED FOR LONG-TERM ENERGY STORAGE AND INSULATION FAT CONTAINS ABOUT 2X AS MUCH ENERGY PER GRAM AS SUGAR

Fatty acid (palmitic acid) Fig. 5-11 Fatty acid (palmitic acid) MEMORIZE THIS RXN FOR TEST! Glycerol (a) Dehydration reaction in the synthesis of a fat Ester linkage Figure 5.11 The synthesis and structure of a fat, or triacylglycerol (b) Fat molecule (triacylglycerol)

3. Steroids include cholesterol and certain hormones Steroids are lipids with a carbon skeleton consisting of four fused carbon rings. Different steroids are created by varying functional groups attached to the rings. Fig. 5.14 Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

CELL MEMBRANES ARE FORMED BY PHOSPHOLIPID BILAYERS Fig. 7-2 CELL MEMBRANES ARE FORMED BY PHOSPHOLIPID BILAYERS WATER Hydrophilic head Hydrophobic tail WATER

Fibers of extracellular matrix (ECM) Glyco- Carbohydrate protein Fig. 7-7 Fibers of extracellular matrix (ECM) Glyco- protein Carbohydrate Glycolipid EXTRACELLULAR SIDE OF MEMBRANE Cholesterol Microfilaments of cytoskeleton Peripheral proteins Integral protein CYTOPLASMIC SIDE OF MEMBRANE

(b) Enzymatic activity (c) Signal transduction Fig. 7-9 Signaling molecule Enzymes Receptor ATP Signal transduction (a) Transport (b) Enzymatic activity (c) Signal transduction Glyco- protein (d) Cell-cell recognition (e) Intercellular joining (f) Attachment to the cytoskeleton and extracellular matrix (ECM)

Table 5.1 An Overview of Protein Functions

GLOBULAR PROTEIN FIBROUS PROTEIN – - roughly spherical, Fig. 5-21g GLOBULAR PROTEIN - roughly spherical, water-soluble Hemoglobin FIBROUS PROTEIN – STRUCTURAL, ROPE-LIKE Iron Figure 5.21 Levels of protein structure—tertiary and quaternary structures Heme  Chains Hemoglobin Collagen

Levels of Protein Structure Primary – sequence of amino acids Secondary- folded patterns produced by hydrogen bonding along amino-acid backbone Tertiary- overall 3-D folding pattern produced by interactions of side-chains Quaternary- interaction between separate amino acid chains of a protein

Figure 5.24 Review: the four levels of protein structure

Fig. 5-UN1  carbon Amino group Carboxyl group

Figure 5.16 Making a polypeptide chain

Figure 5.22 Examples of interactions contributing to the tertiary structure of a protein

Figure 5.23 The quaternary structure of proteins