Macromolecules The molecules of life 1
Organic Chemistry All living things are mostly composed of 6 elements: C, H, N, O, P, S Compounds are broken down into 2 general categories: Inorganic Compounds: Do not contain carbon Organic compounds Contain significant amounts of carbon. Often found with common "functional groups"
Carbon (C) Carbon has 4 electrons in outer shell. Carbon can form covalent bonds with as many as 4 other atoms (elements). Usually with C, H, O or N. Example: CH 4 (methane) 3
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Macromolecules LARGE organic molecules. Also called POLYMERS (poly- means many ) Made up of smaller building blocks called MONOMERS (mono- means one ) 4 types: 1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic acids (DNA and RNA) 5
Monomer vs. Polymer 6
Macromolecules are formed from Dehydration Synthesis Also called condensation reaction Forms polymers by combining monomers by removing water. HO H HO H H 2 O HO H 7
Macromolecules are broken down by Hydrolysis Separates monomers by adding water HO H H 2 O HO H HO H 8
Carbohydrates Carbohydrates are made from simple sugars like: glucose and fructose. Carbohydrates store energy. Examples: A. monosaccharide B. disaccharide C. polysaccharide 9
Carbohydrates Monosaccharide: one sugar unit Examples: glucose (C 6 H 12 O 6 ) deoxyribose glucose ribose Fructose Galactose 10
Carbohydrates Disaccharide: two sugar unit Examples: Sucrose (glucose+fructose) Lactose (glucose+galactose) Maltose (glucose+glucose) glucose glucose 11
Carbohydrates Polysaccharide: many sugar units Examples: starch (bread, potatoes) glycogen (beef muscle) cellulose (lettuce, corn) glucose glucose glucose glucose cellulose glucose glucose glucose glucose 12
Carbohydrates
Lipids Not soluble in water (do not dissolve). Functions: Store the most energy Make up cell membranes Act as chemical messengers (hormones) Protect and insulate Examples: 1. Fats 2. Phospholipids 3. Oils 4. Waxes 5. Steroid hormones 6. Triglycerides 14
Lipids Triglycerides: composed of 1 glycerol and 3 fatty acids. H H-C----O H-C----O H-C----O H O C-CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 3 O C-CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 3 O C-CH 2 -CH 2 -CH 2 -CH fatty acids glycerol 15
Fatty Acids There are two kinds of fatty acids you may see these on food labels: 1. Saturated fatty acids: no double bonds (bad) saturated O C-CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 3 2. Unsaturated fatty acids: double bonds (good) unsaturated O C-CH 2 -CH 2 -CH 2 -CH 16
Lipids
Proteins (Polypeptides) Amino acids (20 different kinds of aa) bonded together by peptide bonds (polypeptides). Functions of proteins: 1. Storage: albumin (egg white) 2. Transport: hemoglobin 3. Regulatory: hormones 4. Movement: muscles 5. Structural: membranes, hair, nails 6. Enzymes: cellular reactions 18
Proteins (Polypeptides) Four levels of protein structure: A. Primary Structure B. Secondary Structure C. Tertiary Structure D. Quaternary Structure 19
Primary Structure Amino acids bonded together by peptide bonds (straight chains) Amino Acids (aa) aa1 aa2 aa3 aa4 aa5 aa6 Peptide Bonds 20
Secondary Structure 3-dimensional folding arrangement of a primary structure into coils and pleats held together by hydrogen bonds. Two examples: Alpha Helix Hydrogen Bonds Beta Pleated Sheet 21
Tertiary Structure Secondary structures bent and folded into a more complex 3-D arrangement of joined poypeptides Bonds: H-bonds, ionic, disulfide bridges (S-S) Call a subunit. Alpha Helix Beta Pleated Sheet 22
Quaternary Structure Composed of 2 or more subunits Globular in shape Form in Aqueous environments Example: enzymes (hemoglobin) subunits 23
Proteins
Nucleic acids Carry the genetic information to make proteins. Two types: a. Deoxyribonucleic acid (DNAdouble helix) b. Ribonucleic acid (RNA-single strand) Nucleic acids are composed of long chains of nucleotides linked by dehydration synthesis. 25
Nucleic acids Nucleotides include: phosphate group pentose sugar (5-carbon) nitrogenous bases: adenine (A) thymine (T) DNA only uracil (U) RNA only cytosine (C) guanine (G) 26
Nucleotide Phosphate Group O O=P-O O CH2 C 4 Sugar (deoxyribose) 5 O C 3 C 2 C 1 N Nitrogenous base (A, G, C, or T) 27
5 DNA - double helix O 3 P 3 O 5 P P 5 4 5 3 O O 1 2 T G A C 2 3 1 O 3 4 5 P P 3 O 5 P 28
Nucleic Acids
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