This chapter presents the following content: An organism's metabolism transform matter and energy, of thermodynamics, The free-energy change of a reaction tells us whether or not the reaction occurs spontaneously, ATP powers cellular work by coupling exergonic reactions to engergonic reactions, enzymes speed up metabolic reactions by lowering energy barriers, regulation of enzyme activity helps control metabolism. | An Introduction to Metabolism Chapter 8 Overview: 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 © 2011 Pearson Education, Inc. Concept : An organism’s metabolism transforms matter and energy, subject to the laws of thermodynamics Metabolism is the totality of an organism’s chemical reactions Metabolism is an emergent property of life that arises from interactions between molecules within the cell © 2011 Pearson Education, Inc. Organization of the Chemistry of Life into Metabolic Pathways A metabolic pathway begins with a specific molecule and ends with a product Each step is catalyzed by a specific enzyme © 2011 Pearson Education, Inc. Figure Enzyme 1 Enzyme 2 Enzyme 3 Reaction 1 Reaction 2 Reaction 3 Product Starting molecule A B C D Figure In-text figure, p. 142 . | An Introduction to Metabolism Chapter 8 Overview: 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 © 2011 Pearson Education, Inc. Concept : An organism’s metabolism transforms matter and energy, subject to the laws of thermodynamics Metabolism is the totality of an organism’s chemical reactions Metabolism is an emergent property of life that arises from interactions between molecules within the cell © 2011 Pearson Education, Inc. Organization of the Chemistry of Life into Metabolic Pathways A metabolic pathway begins with a specific molecule and ends with a product Each step is catalyzed by a specific enzyme © 2011 Pearson Education, Inc. Figure Enzyme 1 Enzyme 2 Enzyme 3 Reaction 1 Reaction 2 Reaction 3 Product Starting molecule A B C D Figure In-text figure, p. 142 Catabolic pathways release energy by breaking down complex molecules into simpler compounds Cellular respiration, the breakdown of glucose in the presence of oxygen, is an example of a pathway of catabolism © 2011 Pearson Education, Inc. Anabolic pathways consume energy to build complex molecules from simpler ones The synthesis of protein from amino acids is an example of anabolism Bioenergetics is the study of how organisms manage their energy resources © 2011 Pearson Education, Inc. Forms of Energy Energy is the capacity to cause change Energy exists in various forms, some of which can perform work © 2011 Pearson Education, Inc. Kinetic energy is energy associated with motion Heat (thermal energy) is kinetic energy associated with random movement of atoms or molecules Potential energy is energy that matter possesses because of its location or structure Chemical energy is potential energy available for release in a chemical reaction Energy can be converted from one form to .
