Thermodynamics Energy Transfer Cells

Thermodynamics and Energy Transfer in Cells Biology Concept Teaching Ryan Finn Concept Survival of organisms depends on their ability to do work Work is the ability to perform physical tasks Work = Force x Distance Energy is used to do work Energy and Living Organisms Living things use energy to do work in order to survive Energy resides at the molecular level Chemical reactions: Catabolic Anabolic Metabolism Types of Energy Organisms gather energy in many forms: Light, sound, and chemical Two basic types of energy to consider: Kinetic Energy Potential Energy 1st Law of Thermodynamics The total amount of energy in the universe is constant. Energy cannot be created or destroyed but only converted from one form into another. If an object or process gains an amount of energy, it does so at the expense of a loss in energy somewhere else in the universe. Diver Potential Energy Diver: Gravitational potential energy Living Cell: Chemical potential energy Bond Energy Bond Energy Cont. Breaking Bonds Energy required to break a bond Creating Bonds Energy released when a bond forms Types of Reactions Exothermic Reactions the energy of the products is less than the energy of the reactants Endothermic Reactions the energy of the products is more than the energy of the reactants Exothermic Reaction Endothermic Reactions Online Resource Potential Energy Diagram Online http://phet.colorado.edu/en/simulation/reversible-reactions#teaching-ideas Enthalpy The difference of energy between the beginning of a reaction and the end Also referred to as the heat of a reaction Represented by ?H Entropy Measure of disorder in the universe Represented by ?S Entropy in Chemical Reactions Entropy increases when: Solid reactants become liquid or gaseous Liquid reactants become gaseous products Fewer moles of reactant molecules form a greater number of moles of product molecules Complex molecules react to form simpler molecules Diffusion Entropy Free Energy Josiah Willard Gibbs Gibbs Free Energy Energy that can do useful work Free Energy Demonstration Will it occur? ?G = (?H) – (K) (?S) ?G = (- ?H) – (+ K) ( +?S) ?G = (-) – (+ ) ?G = - Negative 2nd Law of Thermodynamics The entropy of the universe increases with any change that occurs Also referred to as the Law of Entropy Applied to Biology Violate of 2nd law of thermodynamics Obey the 2nd law of thermodynamics ATP ATP is the primary source of free energy in living cells Redox Reactions Oxidation Reduction Reducing Agent Oxidizing Agent Leo lion says Ger Redox Reactions