BIOL 111 1st EditionExam 2 Study Guide- Metabolismo Energy—the capacity to do work or cause Change Types of energy- Kinetic—energy due to motiono Ex: light, heat, sound- Potential—energy stored due to position or structureo Ex: chemical, atomic- Measuring energyo Calorie (cal) = amt. heat required to raise 1 g of water 1ºC Kcal = 1000 cal = Calorie (in food)- Thermodynamicso Studying energy flow in natural systems 1st Law-Energy and matter can be transferred but cannot be created or destroyed. 2nd Law-In every energy transfer, some energy becomes unusable (heat), which increases entropy or disorder of the universe.- Spontaneous Reactionso Require no input of energyo Increases entropy- Gibbs Free Energyo Measures the energy in a “system” (ex: living cell)o Value of ΔG will predict spontaneity of a reactiono ΔG = ΔH – T ΔS ΔG: change in free energy (E avail for work) ΔH: change in enthalpy (potential E) T: temperature measured in degrees Kelvin ΔS: change in entropy- —ΔG = spontaneouso Exergonic--net release of free energy o Products are more stable but w/ less free energy- + ΔG = NOT spontaneouso Endergonic—absorbs/stores free energyo Products are less stable but w/ more free energy- Metabolismo Chemical reactions in a cell required to maintain life.o Types of metabolism: Anabolic-building molecules, requires energy Catabolic-breaking down molecules, produces energy- Enzymes-catalytic proteins, not consumed in reactiono Active site• Have precise physical shape for specific reactants/substrates• Site of catalysis provides microenvironment• Changes shape to form induced fit• Applies force to break bonds, form new bonds- Measuring enzyme activityo How did you measure the rate of reaction in lab?o Spectrophotometer Measures?-either transmitted or absorbed light How?-molecules absorb lighto Enzymes alter molecules thus alter light absorbing properties.- Rates of Reaction Varyo Enzyme concentrationo Substrate concentrationo Temperatureo pH- Rates of Reaction Varyo Cofactors: nonprotein molecules aid enzyme catalysis Inorganic: metal ions Organic: coenzymes, from vitaminso Inhibitorso Allosteric Regulation- Inhibitorso Chemicals that inactivate enzyme activityo Competitive: bind active siteo Non-competitive: bind other site, but alters active site- Allosteric Regulationo Examples: Hemoglobin 4 polypeptides each bind O2 or CO2 cooperative binding of O2 or CO2 o Reversible binding, loses affinityo Binding of molecule to protein at one site that affects protein function at another site. Examples:- ADP = catabolic enzyme activator- ATP = catabolic enzyme inhibitor- Review quizo What do you need to remove pairs of e-?o What are the net products of glycolysis?o Name 3 enzymes and 4 substrates you need to know from glycolysis. Enzymes: hydrogenase, isomenase, pysomerase Substrates: glucose, pyruvate, G3P, DHAP- Review/Previewo Energy Mattero Redox rxnso Laws of Thermodynamicso Kinetic vs. Potential energy o Follow carbons o Follow electronso Carbon cycleo Electron transport chain & chemiosmosiso ATP synthase- Reviewo 1. Which parts of the chloroplast are we concentrating on? Why?o 2. Which wavelengths are absorbed by the pigments in the chloroplast?o 3. What is the primary purpose of the “light reactions”?o 4. What is the source of the electrons for the “light reactions”?o 5. Describe electron flow during the light reactions.o 6. Where is the high H+ concentration in a chloroplast?o 7. What is the purpose of cyclic electron
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