CWRU-BIO215-Exam 2 (Graded A+ actual test)

energy - capacity to do work Compare potential energy and kinetic energy. Classify different energy forms into one of these two categories - potential energy is the possibility to do work: -chemical potential -concentration gradient -gravitational -stored mechanical kinetic energy -electrical -sound -radiant -thermal -motion Explain why cells need energy? Describe the types and examples of cellular work. - 1. synthetic work 2. mechanical work 3. concentration work 4. electrical work 5. generation of heat 6. generation of light Explain how energy and matter are used in the biosphere. Specifically explain this statement: "Energy flows through the biosphere while matter is recycled". -autotroph - an organism that produces its own energy though light and inorganic chemical reactions heterotroph - an organism that uses organic carbons for its growth chemotroph - heterotroph that uses chemicals for energy phototroph - heterotroph that uses light for energy thermodynamics - take energy from 1 form and transfer it to another 1st law of thermodynamics - energy cannot be created or destroyed but it can be transformed 2ed law of thermodynamics - energy transformation goes towards higher disorder (entropy) of a system free energy in a spontaneous process - a spontaneous process occurs when there is a -ΔG, -ΔH, and +ΔS so a decrease in free energy is exothermic and more disordered. Spontaneous processes are exergonic ΔG - tells us the free energy in a system / the amount of energy available to do work if ΔG=0 the system is at equilibrium Gibbs's free energy formula - ΔG= free energy ΔS= change in entropy ( disorder) ΔH= change in enthalpy (heat) T= temperature in K Keq (equilibrium constant) - ΔG is a measure of how far a reaction is from reaching equilibriumIntemperate a free energy diagram - when the Reactants have a higher free energy they releases energy when making the products and this process is spontaneous when the reactants have a lower free energy than the products the process is non spontaneous and requires energy Activation energy barrier (Eₐ ) and how it influences the rate of reaction - Eₐ is the minimum amount of energy of the reactants required in order for a reaction to take place the higher the Eₐ the slower the reaction Metabolism - total collection of chemical reactions that take place in a cell catabolic pathways - break things down (exergonic spontaneous process) anabolic pathways - synthesize things (endergonic non spontaneous) energy coupling - cells use energy created from catabolic pathways to fuel anabolic pathways which drives an unfavorable process by giving them the energy they need to happen ATP structure - ATP function - to provide energy to the cell when a bond on the phosphate is broken it releases energy and the ATP becomes ADP phosphorylase enzyme - catalyses the addition of a phosphate group to molecules with inorganic phosphate Pᵢ kinase enzymes - catalyses the addition of a phosphate group to target molecules (usually protein molecules)Phosphatase enzymes - catalyze the hydrologic removal of phosphate groups from a target Why ATP - ATP is right int eh middle in terms of how much energy it releases so it requires the least amount of reactions to reform ATP opposing charges resonance destabilization free energy of hydrolysis