AP Biology Mrs. Ramon

The Molecules of Life Macromolecules LARGE molecules Four classes: 1. Carbohydrates 2. Lipids (Fats) 3. Proteins 4. Nucleic Acids How are macromolecules made? Activity: Making and Breaking Polymers

Carbohydrates Functions Fuel Binding material Monomer Monosaccharides (CH 2 O) Polymer Polysaccharides Bond Glycosidic linkage Activity: Carbohydrates

Fig. 5-3 Dihydroxyacetone Ribulose Ketoses Aldoses Fructose Glyceraldehyde Ribose Glucose Galactose Hexoses (C 6 H 12 O 6 ) Pentoses (C 5 H 10 O 5 ) Trioses (C 3 H 6 O 3 )

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

Fig. 5-9

Fig The structure of the chitin monomer. (a) (b) (c) Chitin forms the exoskeleton of arthropods. Chitin is used to make a strong and flexible surgical thread.

Lipids Components Glycerol and fatty acids Bond Ester linkage Three types: 1. Fats 2. Phospholipids 3. Steroids

Fig Fatty acid (palmitic acid) Glycerol (a) Dehydration reaction in the synthesis of a fat Ester linkage (b) Fat molecule (triacylglycerol)

Fig Structural formula of a saturated fat molecule Stearic acid, a saturated fatty acid (a) Saturated fat Structural formula of an unsaturated fat molecule Oleic acid, an unsaturated fatty acid (b) Unsaturated fat cis double bond causes bending

Fig (b) Space-filling model (a)(c) Structural formula Phospholipid symbol Fatty acids Hydrophilic head Hydrophobic tails Choline Phosphate Glycerol Hydrophobic tails Hydrophilic head

Fig Hydrophilic head Hydrophobic tail WATER

Fig. 5-15

Proteins Functions Structure Storage Transport Hormones Signaling Movement Defense Enzymatic Monomer Amino acid Polymer Polypeptide Bond Peptide bond

Fig Enzyme (sucrase) Substrate (sucrose) Fructose Glucose OH H O H2OH2O

Fig. 5-UN1 Amino group Carboxyl group  carbon

Fig. 5-17a Nonpolar Glycine (Gly or G) Alanine (Ala or A) Valine (Val or V) Leucine (Leu or L) Isoleucine (Ile or I ) Methionine (Met or M) Phenylalanine (Phe or F) Tryptophan (Trp or W) Proline (Pro or P)

Fig. 5-17b Polar Asparagine (Asn or N) Glutamine (Gln or Q) Serine (Ser or S) Threonine (Thr or T) Cysteine (Cys or C) Tyrosine (Tyr or Y)

Fig. 5-17c Acidic Arginine (Arg or R) Histidine (His or H) Aspartic acid (Asp or D) Glutamic acid (Glu or E) Lysine (Lys or K) Basic Electrically charged

Fig A ribbon model of lysozyme (a)(b) A space-filling model of lysozyme Groove

Fig Antibody protein Protein from flu virus

Fig Primary Structure Secondary Structure Tertiary Structure  pleated sheet Examples of amino acid subunits + H 3 N Amino end  helix Quaternary Structure

Fig. 5-21f Polypeptide backbone Hydrophobic interactions and van der Waals interactions Disulfide bridge Ionic bond Hydrogen bond

Fig. 5-21g Polypeptide chain  Chains Heme Iron  Chains Collagen Hemoglobin

Fig Primary structure Secondary and tertiary structures Quaternary structure Normal hemoglobin (top view) Primary structure Secondary and tertiary structures Quaternary structure Function  subunit Molecules do not associate with one another; each carries oxygen. Red blood cell shape Normal red blood cells are full of individual hemoglobin moledules, each carrying oxygen. 10 µm Normal hemoglobin     Val His Leu ThrPro Glu Red blood cell shape  subunit Exposed hydrophobic region Sickle-cell hemoglobin   Molecules interact with one another and crystallize into a fiber; capacity to carry oxygen is greatly reduced.   Fibers of abnormal hemoglobin deform red blood cell into sickle shape. 10 µm Sickle-cell hemoglobin GluPro Thr Leu His Val

Fig. 5-22c Normal red blood cells are full of individual hemoglobin molecules, each carrying oxygen. Fibers of abnormal hemoglobin deform red blood cell into sickle shape. 10 µm

Fig Normal protein Denatured protein Denaturation Renaturation

Nucleic Acids Functions Genetic info. Monomer Nucleotide Polymer Polynucleotides Bond Phosphodiester linkage

Fig mRNA Synthesis of mRNA in the nucleus DNA NUCLEUS mRNA CYTOPLASM Movement of mRNA into cytoplasm via nuclear pore Ribosome Amino acids Polypeptide Synthesis of protein 1 2 3

Fig end Nucleoside Nitrogenous base Phosphate group Sugar (pentose) (b) Nucleotide (a) Polynucleotide, or nucleic acid 3 end 3C3C 3C3C 5C5C 5C5C Nitrogenous bases Pyrimidines Cytosine (C) Thymine (T, in DNA)Uracil (U, in RNA) Purines Adenine (A)Guanine (G) Sugars Deoxyribose (in DNA) Ribose (in RNA) (c) Nucleoside components: sugars

Fig Sugar-phosphate backbones 3' end 5' end Base pair (joined by hydrogen bonding) Old strands New strands Nucleotide about to be added to a new strand

Fig. 5-UN9

You should now be able to: 1. List and describe the four major classes of molecules 2. Describe the formation of a glycosidic linkage and distinguish between monosaccharides, disaccharides, and polysaccharides 3. Distinguish between saturated and unsaturated fats 4. Describe the four levels of protein structure 5. Distinguish between the following pairs: pyrimidine and purine, nucleotide and nucleoside, ribose and deoxyribose, the 5 end and 3 end of a nucleotide Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings