Introduction to metabolic pathways

Introduction to metabolic pathways Babylon universityCollege of pharmacySecond semester 3rdclass Biochemistry Assist prof. Dr. Abdulhussien M. Aljebory
Objectives•Explain the role of catabolic and anabolic pathways in cell metabolism•Distinguish between kinetic and potential energy•Distinguish between open and closed systems•Explain the first and second Laws of Thermodynamics•Distinguish between entropy and enthalpy•Understand the Gibbs equation for free energy change•Understand how “usable” energy changes with changes in enthalpy, entropy, and temperature•Understand the usefulness of free energy How to Read a Chemical Equation•A chemical reaction starts with reactants and finishes with products:C6H1206+ 6O2 ?6CO2+6H20 + ENERGYreactantproduct6CO2+6H20 + light?C6H1206+ 6O2•Disturbing either the concentration or the energy of the system alters the chemical equilibrium. Living things NEVER let their reactions go to equilibrium The Energy of Life•The living cell is a miniature chemical factory where thousands of reactions occur•The cell extracts energy and applies energy to perform work•Some organisms even convert energy to light, as in bioluminescence An organism’s metabolism transforms matter and energy, subject to the laws of thermodynamics•Metabolismis the totality of an organism’s chemical reactions•Metabolism is an emergent property of life that arises from interactions between molecules within the cell•A metabolic pathway begins with a specific molecule (reactant) and ends with a product•Each step is catalyzed by a specific enzyme