BIO 151 1st Edition Lecture 4 Outline of Last Lecture 1. What is in the water in living cells?2. Carbon-containing organic molecules3. Structural question: will an organic molecule dissolve in water?4. Hydrophobic interactions5. Chemical bonds6. Carbon-containing "organic" molecules7. Examples of chemical reactions8. Molecules contain potential energy in bonds, electrons9. What makes a reaction "spontaneous" (favored)?10. Enzymes - biological catalysts (speed chemicals reactions)Outline of Current Lecture1. Polymers and carbohydrates2. Enzymes3. Chemical equilibrium4. Many cells get energy from organic molecules = food5. What about early earth? What chemicals were present?6. Energy is needed to build more complex molecules7. Miller8. Important large organic molecules = macromolecules9. Polymer macromolecules10. Hydrocarbons11. Carbohydrates12. Monosaccharides can be joined by...Current Lecture MacromoleculesPolymers and Carbohydrates:- Big organic molecules used for --structure (and movement)-reactants to make other molecules-energy in bonds, electrons-control other chemical reactionsEnzymes:These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- biological catalysts that speed (and thus control) specific chemical reactions- energy of activation is lowered- EA required to form an "active" intermediate in the reaction- not stored- used, then released by reaction- exergonic - spontaneous reaction release free energy.- endergonic - non-spontaneous reactions absorb free energy-when you add a catalyst to a reaction at equilibrium, nothing changesChemical equilibrium:- "reduced" carbon has more energy than "oxidized" carbon because it has higher electrons in bonds-reduction-oxidation (REDOX) reaction couples the two- reduced - reduces charged- oxidized - loses electrons- carbon "oxidized" even when electron just moves further away- can release energy- more "reduced" carbons have more useful potential energy in electrons- CH4 = methane, carbon "reduced," high PE- CO2 = carbon dioxide, carbon "oxidized," lower PEMany cells get energy from organic molecules = food:- some cells can also get energy from:-sunlight (photosynthesis)-grab high-energy electrons from a few inorganic molecules-radiation (rare)What about early earth? What chemicals were present?:- water, water vapor-dissolved ions, minerals- volcanic gases: CO2, carbon monoxide (CO), perhaps CH4- nitrogen (N2, perhaps NH3)- perhaps hydrogen (H2)- little oxygen gas (O2)Energy is needed to build more complex molecules:- in atmosphere --solar radiation-electrical energy - lightning- in oceans --thermal energy at hydrothermal vents- in rocks --radioactive decayMiller:- methane, ammonia, hydrogen, water- got hydrogen cyanide, formaldehyde, amino acidsImportant large organic molecules = macromolecules:- carbohydrates- proteins- nucleic acids-these 3 are polymers made by linking specific monomers- lipids - biggish, and mostly hydrophobic, not a polymerPolymer macromolecules:- polymers = a chain of similar monomer subunits- dehydration (condensation) reaction - break down polysaccharides and monosaccharides via hydrolysis (add a water molecule, breaking a bond)Hydrocarbons:- chains and rings - just hydrogen and carbon- but can add different "functional groups" with other atomsCarbohydrates:- add many hydroxyl groups and one carbonyl group to short hydrocarbon chains - monosaccharides (monomer)- can make a ring in water via C-O-C bond- monosaccharides differ by number of carbons, arrangement of OH- and COH-- "something-ose" glucose in honey, fructose in fruit, ribose, etc.- one use of carbohydrates: energy- break up of monosaccharide, get energy-every step uses a different enzyme- reverse: build monosaccharides, store energyMonosaccharides can be joined by...- glycosidic linkage (C-O-C) into disaccharides (2), polysaccharides (many)- sucrose (table sugar) = disaccharide- starch =
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