1 Macromolecules copyright cmassengale

2 Organic Compounds CompoundsCARBON organicCompounds that contain CARBON are called organic. Macromoleculesorganic moleculesMacromolecules are large organic molecules. copyright cmassengale

3 Carbon (C) Carbon4 electronsCarbon has 4 electrons in outer shell. Carboncovalent bonds 4Carbon can form covalent bonds with as many as 4 other atoms (elements). C, H, O or NUsually with C, H, O or N. Example:CH 4 (methane)Example:CH 4 (methane) copyright cmassengale

4 Macromolecules Large organic molecules.Large organic molecules. POLYMERSAlso called POLYMERS. MONOMERSMade up of smaller “building blocks” called MONOMERS. Examples:Examples: 1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic acids (DNA and RNA) copyright cmassengale

5 Question: How Are Macromolecules Formed? copyright cmassengale

6 Answer: Dehydration Synthesis “condensation reaction”Also called “condensation reaction” polymers monomers“removing water”Forms polymers by combining monomers by “removing water”. HOH HH H2OH2O copyright cmassengale

7 Question: How are Macromolecules separated or digested? copyright cmassengale

8 Answer: Hydrolysis monomers“adding water”Separates monomers by “adding water” HO HH H H2OH2O copyright cmassengale

9 Carbohydrates

10 Carbohydrates Small sugar moleculeslarge sugar moleculesSmall sugar molecules to large sugar molecules. Composed of the elements C,H,O in a 1:2:1 ratio Examples:A.monosaccharide B.disaccharideExamples:A.monosaccharide B.disaccharide C.polysaccharide copyright cmassengale

11 Carbohydrates Monosaccharide: one sugar unit Examples:glucose ( Examples:glucose (C 6 H 12 O 6 )deoxyriboseriboseFructoseGalactose glucose copyright cmassengale

12 Carbohydrates Disaccharide: two sugar unit Examples: –Sucrose (glucose+fructose) –Lactose (glucose+galactose) –Maltose (glucose+glucose) glucoseglucose copyright cmassengale

13 Carbohydrates Polysaccharide: many sugar units Examples:starch (bread, potatoes) glycogen (beef muscle) cellulose (lettuce, corn) glucoseglucose glucoseglucose glucoseglucose glucoseglucose cellulose copyright cmassengale

14 Lipids copyright cmassengale

15Lipids not soluble in waterGeneral term for compounds which are not soluble in water. are soluble in hydrophobic solventsLipids are soluble in hydrophobic solvents. Elements: C,H ratio 1:2 very little O Remember:“stores the most energy”Remember: “stores the most energy” Examples:1. FatsExamples:1. Fats 2. Phospholipids 3. Oils 4. Waxes 5. Steroid hormones 6. Triglycerides copyright cmassengale

16 Lipids Six functions of lipids: 1.Long term energy storage 2.Protection against heat loss (insulation) 3.Protection against physical shock 4.Protection against water loss 5.Chemical messengers (hormones) 6.Major component of membranes (phospholipids) copyright cmassengale

17 Lipids Triglycerides: c1 glycerol3 fatty acids Triglycerides: composed of 1 glycerol and 3 fatty acids. H H-C----O H glycerol O C-CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 3 = fatty acids 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 =CH-CH 2 -CH 2 -CH 2 -CH 2 -CH 3 = copyright cmassengale

18 Fatty Acids fatty acids There are two kinds of fatty acids you may see these on food labels: 1.Saturated fatty acids: no double bonds (bad) 2.Unsaturated fatty acids: double bonds (good) O C-CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 3 = saturated O C-CH 2 -CH 2 -CH 2 -CH =CH-CH 2 -CH 2 -CH 2 -CH 2 - CH 3 = unsaturated copyright cmassengale

19 Proteins copyright cmassengale

20 Proteins (Polypeptides) peptide bonds polypeptidesAmino acids (20 different kinds of aa) bonded together by peptide bonds (polypeptides). Elements: C,H,O,N –no ratio Six functions of proteins:Six 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 copyright cmassengale

21 Proteins (Polypeptides) Four levels of protein structure: A.Primary Structure B.Secondary Structure C.Tertiary Structure D.Quaternary Structure copyright cmassengale

22 Primary Structure peptide bonds (straight chains) Amino acids bonded together by peptide bonds (straight chains) aa1aa2aa3aa4aa5aa6 Peptide Bonds Amino Acids (aa) copyright cmassengale

23 Secondary Structure primary structurecoilspleats hydrogen bonds3-dimensional folding arrangement of a primary structure into coils and pleats held together by hydrogen bonds. Two examples:Two examples: Alpha Helix Beta Pleated Sheet Hydrogen Bonds copyright cmassengale

24 Tertiary Structure Secondary structuresbentfolded more complex 3-D arrangementSecondary structures bent and folded into a more complex 3-D arrangement of linked polypeptides Bonds: H-bonds, ionic, disulfide bridges (S-S)Bonds: H-bonds, ionic, disulfide bridges (S-S) “subunit”.Call a “subunit”. Alpha Helix Beta Pleated Sheet copyright cmassengale

25 Quaternary Structure Composed of 2 or more “subunits” Globular in shape Form in Aqueous environments enzymes (hemoglobin)Example: enzymes (hemoglobin) subunits copyright cmassengale

26 Nucleic Acids copyright cmassengale

27 Nucleic acids Two types:Two types: a. Deoxyribonucleic acid (DNA- double helix) b. Ribonucleic acid (RNA-single strand) b. Ribonucleic acid (RNA-single strand) Nucleic acids nucleotides dehydration synthesisNucleic acids are composed of long chains of nucleotides linked by dehydration synthesis. Elements: C,H,O,N,P – no ratio copyright cmassengale

28 Nucleic acids Nucleotides include:Nucleotides include: phosphate group pentose sugar (5-carbon) nitrogenous bases: adenine (A) thymine (T) DNA only uracil (U) RNA only cytosine (C) guanine (G) copyright cmassengale

29 Nucleotide O O=P-O OPhosphate Group Group N Nitrogenous base (A, G, C, or T) (A, G, C, or T) CH2 O C1C1 C4C4 C3C3 C2C2 5 Sugar Sugar(deoxyribose) copyright cmassengale

30 DNA - double helix P P P O O O P P P O O O G C TA copyright cmassengale

pH Scale We use this scale to measure the strength of an acid or base. pH is defined as the –log[H+] pH can use the concentration of hydronium ions or hydrogen ions.

pH Scale Acid Base Zumdahl, Zumdahl, DeCoste, World of Chemistry  2002, page 515

pH of Common Substances Timberlake, Chemistry 7 th Edition, page 335

Acid – Base Concentrations pH = 3 pH = 7 pH = 11 OH - H3O+H3O+ H3O+H3O+ H3O+H3O+ [H 3 O + ] = [OH - ] [H 3 O + ] > [OH - ] [H 3 O + ] < [OH - ] acidic solution neutral solution basic solution concentration (moles/L) Timberlake, Chemistry 7 th Edition, page 332

Water Chemistry A. _Water__ is the most abundant chemical in the body. B. Water has many characteristics that make it vital to our bodies. –1. _Size_—water is a very small molecule, so it moves fast and can squeeze into tiny crevasses between other molecules.

II. Water Chemistry B. Water has many characteristics that make it vital to our bodies. –2. Polarity____-- Hydrogen has a slightly positive charge while oxygen has a slightly negative charge. This makes it easy for water to pry apart other charged molecules, dissolving them. Called a __Universal Solvent___.

II. Water Chemistry B. Water has many characteristics that make it vital to our bodies. –3. _Crystal Structure__--Due to polarity, water forms a crystal structure that is less dense than liquid water.

II. Water Chemistry B. Water has many characteristics that make it vital to our bodies. –4. _Heat Capacity__--water absorbs and releases heat energy slowly, and can hold a great deal of heat energy. This helps organisms maintain their body temperature in the safe range.

II. Water Chemistry B. Water has many characteristics that make it vital to our bodies. –5. __Cohesion & Adhesion_____-- Polarity allows water to stick to itself (cohesion) and to any charged material (adhesion). Water can glue materials together.

II. Water Chemistry B. Water has many characteristics that make it vital to our bodies. –6. Buffer___--Water can act as either an acid or a base, maintaining a stable pH in our bodies.

41 Enzymes

42 What Are Enzymes? Proteins (Most enzymes are Proteins (tertiary and quaternary structures) CatalystAct as Catalyst to accelerates a reaction Not permanentlyNot permanently changed in the process

43Enzymes catalyzeAre specific for what they will catalyze ReusableAre Reusable aseEnd in –ase-Sucrase-Lactase-Maltase

44 How do enzymes Work? weakening bonds which lowers activation energy Enzymes work by weakening bonds which lowers activation energy

45 Enzyme-Substrate Complex substance enzyme substrate The substance (reactant) an enzyme acts on is the substrate Enzyme Substrate Joins

46 Active Site restricted region enzymebinds substrateA restricted region of an enzyme molecule which binds to the substrate. Enzyme Substrate Active Site

47 Induced Fit changeconfiguration enzyme’s active siteA change in the configuration of an enzyme’s active site (H+ and ionic bonds are involved). Inducedsubstrate.Induced by the substrate. Enzyme Active Site substrate induced fit

48 What Affects Enzyme Activity? Three factors:Three factors: 1.Environmental Conditions 2.Cofactors and Coenzymes 3.Enzyme Inhibitors

49 1. Environmental Conditions 1. Extreme Temperature are the most dangerous 1. Extreme Temperature are the most dangerous - high temps denature (unfold) enzyme. - high temps may denature (unfold) the enzyme. 2.pH (most like pH near neutral) 3.Ionic concentration (salt ions)