Chapter 6
Explain what free energy is and how it can be used to predict the energetic outcome of chemical reactions.Free energy is defined as the energy available to do work in any system. The free energy is denoted by the symbol G. G = H – TS* H: the energy contained in a molecule’s chemical bonds, called enthalpy.* TS: the energy term related to the degree of disorder in the system. T is the absolute temperature (K), and S is the entropy.We can use the change in free energy to predict whether a chemical reaction is spontaneous or not:- G positive: the products contain more free energy than the reactants. The bond energy (H) is higher, or the disorder (S) is lower. Therefore, the reaction is NOT spontaneous because it requires the
At higher temperatures, these forces are to weak to maintain the enzyme shape, and it denatures. -PH: Ionic interaction between oppositely charged amino acids hold the enzymes together. When hydrogen ion concentration is shifted, the balanced is shifted as well (+/-) Most enzymes optimum pH is between 6-8. - Inhibitors and activators: They regulate when enzymes are active/inactive at a given time. Competitive inhibitors compete with the substrate for the same active site, preventing substances from binding. Noncompetitive inhibitors bind to the enzyme in a location other than the active site, changing the shape. Allosteric inhibitors bind to the allosteric site, and can also be activators increasing the enzyme’s activity.
Schematize the relationships between: energy, biological reactions, and enzyme function-Anabolism: YES energy, to create larger molecule.-Catabolism: NO energy, to create smaller molecules.Metabolism is the sum of all chemical reactions in a cell. Biochemical pathways organize chemical reactions, using the product of one as the substrate for the other.
Chapter 7
Interpret the role of electrons, electron carriers, and ATP in energy metabolism*Electrons: Energy in metabolism flows in terms of electrons. If electrons are lost, this is called oxidation. If electrons are gained, this is called reduction. Oxidation is coupled to reduction.*Electron carriers: During respiration,