Exam 3 Study Guide: Room A101 of Life Sciences Building Annex. Oct 29th from 7-8:30pmChapter 8:Understand the difference between anabolic and catabolic pathwaysAnabolic pathways build molecules.Catabolic pathways break molecules down.Understand the first 2 laws of thermodynamics and how they relate to energy exchange1. energy cannot be created or destroyed, it can only be transferred and transformed2. with every transfer of energy, some energy escapes as heatKnow the Free Energy equation, and be able to calculate ΔGdeltaG = deltaH – TdeltaSdeltaG: change in free energy (energy available to do work), Gp - GrdeltaH: enthalpy, total energydeltaS: change in entropyTdeltaS: energy not available to do workKnow the characteristics of endergonic and exergonic reactionsEndergonic: non-spontaneous, energetically uphill, products have more energy than reactants, positive deltaGExergonic: spontaneous, energetically downhill, reactants have more energy than the products, negative deltaGUnderstand how ATP hydrolysis provides energy for endergonic reactionsATP + H2O ADP+ PiThis is an extremely exergonic reaction. Releases 7.3 kcal/mol. This energy has to go somewhere… so it’s used to power reactions that require energyUnderstand how enzymes catalyze chemical reactionsLower the activation energy. Don’t affect the free energy of the reactants or the products. Understand the different types of enzyme inhibitors and how they workCompetitive: compete with the substrate and actually bind to the active site of an enzymeAllosteric (non-competitive): bind to a site on the enzyme separate from the active site. Causes achange in the shape of the active site, preventing the substrate from bindingChapter 9:Understand what happens during redox reactionsOxidation-Reduction reaction: involves the transfer of electrons from one atom to another. It’s called reduction because electrons are negative and the total charge of an atom that receives anelectron gets reduced.Oxidized: the atom that loses the electronReduced: the atom that receives the electronNa(e-) + Cl Na+ + Cl(e-) : Na oxidized, Cl reduced, Na reducing agent, Cl oxidizing agentBe able to define oxidizing and reducing agentsOxidizing agent will receive an electron and allow another atom to be oxidized.Reducing agent will donate an electron and allow another atom to be reduced.Understand what happens during fermentation, and why our cells perform this reactionThere is NOT enough oxygen to perform cellular respiration. So, the products from glycolysis (2 pyruvates) get reduced to regenerate NAD+, which is needed for glycolysis. This allows glycolysisto continue to produce ATP in the absence of oxygen.Understand what happens during glycolysis, the bridge reaction, Kreb’s cycle, and oxidative phosphorylation, including the inputs, outputs, location, and O2 requirementsGlycolysis: happens in cytoplasm, no O2 requiredInput: glucose Output: 2 pyruvates, 2 NADH and 2 net ATP’sEnergy investment phase: 2 ATP’s are used to phosphorylate glycolysis intermediatesEnergy harvest phase: glucose gets split, producing 4 ATP’sBridge reaction: happens in the mitochondrial matrix, O2 requiredInput: 2 pyruvates Output: 2 acetyl coA’s, 2 NADHKerb’s Cycle: happens in the mitochondrial matrix, O2 required (2 turns are needed to completely breakdown one glucose molecule)Input: 2 acetyl coA’s Output: 4 NADH, 2 FADH2, 2 ATP’sElectron Transport Chain (Oxidative Phosphorylation): happens in the inner mitochondrial membrane, O2 requiredInput: electrons from NADH and FADH2 Output: ATP and H2OUnderstand chemiosmosis and what occurs during this processElectrons from NADH and FADH2 are donated to the electron transport chain. Electrons get transferred to increasingly EN molecules. Each transfer releases energy. This energy is used to actively transport protons (H+) from the matrix to the inter-membrane space. This builds a proton gradient. Protons will naturally diffuse down their concentration gradient, back into the matrix, activating the enzyme ATP synthase in the process. This allows for ATP to be produced. At the end of the ETC, the electrons are transferred to oxygen, creating water.Chapter 10:Have a general understanding of the goal of photosynthesis and what happens during this processThis is a redox reaction that requires CO2, H2O, and sunlight. Electrons are getting transferred from a more EN molecule (water) to a less EN molecule (CO2). This requires energy, which comes from sunlight. This produced sugar (glucose) and Oxygen.Understand what happens during the Light-dependent reaction, including each individual photosystem and electron transport chain. Know why water gets split during this reaction. Understand the inputs, outputs, location, and time that this reaction occurs.Occurs in the thylakoid membrane, because this is where chlorophyll absorbs sunlight. Only happens in the daytime. There are two photosystems: (I and II). Each photosystem has its own ETC. PSII generates ATP through chemiosmosis. PSI generates NADPH, which carries electrons needed for the Calvin Cycle.Chemiosmosis: protons get pumped inside the thylakoid, building a proton gradient. Protons willnaturally diffuse out of the thylakoid and into the stroma, activating ATP synthase in the process, and producing ATP.Electrons from PSII end up in PSI. Electrons from PSI end up in NADPH. So, water has to be split to resupply electrons to PSII, so the cycle can continue. Otherwise, PSII would eventually run outof electrons.Understand the relationship between wavelength and energy level for different colors of visible lightThe shorter the wavelength, the higher the energy.Understand what happens during each stage of the Calvin cycle, including what NADPH and ATP are used for. Know the inputs, outputs, location, and time that the Calvin Cycle occurs.Light-independent reaction: happens in the stroma, and happens 24/71. Carbon fixation: where CO2 from the atmosphere is absorbed and added to RuBP (a 5 carbon molecule). Carbon is the building material for glucose (like wood for a house). When Carbon gets added to RuBP it produces an intermediate called PGA.2. PGA gets converted to G3P (another intermediate). This step requires energy from ATP and electrons from NADPH.3. Glucose gets produced using two G3P molecules. G3P is a 3-carbon molecule. The remaining G3P molecules get recombined to produce RuBP, which is essential for step 1 so the Calvin Cycle can continue. ADP and NADP+
View Full Document
Unlocking...