tailieunhanh - Lecture Biology (6e): Chapter 6 - Campbell, Reece
Chapter 6 - An introduction to metabolism. This chapter presents the following content: The chemistry of life is organized into metabolic pathways, organisms transform energy, the energy transformations of life are subject to two laws of thermodynamics, organisms live at the expense of free energy, ATP powers cellular work by coupling exergonic reactions to endergonic reactions. | CHAPTER 6 AN INTRODUCTION TO METABOLISM Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section A: Metabolism, Energy, and Life 1. The chemistry of life is organized into metabolic pathways 2. Organisms transform energy 3. The energy transformations of life are subject to two laws of thermodynamics 4. Organisms live at the expense of free energy 5. ATP powers cellular work by coupling exergonic reactions to endergonic reactions The totality of an organism’s chemical reactions is called metabolism. A cell’s metabolism is an elaborate road map of the chemical reactions in that cell. Metabolic pathways alter molecules in a series of steps. 1. The chemistry of life is organized into metabolic pathways Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. The inset shows the first two steps in the catabolic pathway that breaks down glucose. Enzymes selectively accelerate each step. The activity of enzymes is regulated to maintain an appropriate balance of supply and demand. Catabolic pathways release energy by breaking down complex molecules to simpler compounds. This energy is stored in organic molecules until it needs to do work in the cell. Anabolic pathways consume energy to build complicated molecules from simpler compounds. The energy released by catabolic pathways is used to drive anabolic pathways. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Energy is fundamental to all metabolic processes, and therefore to understanding how the living cell works. The principles that govern energy resources in chemistry, physics, and engineering also apply to bioenergetics, the study of how organisms manage their energy resources. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Energy is the capacity to do work - to move matter against opposing forces. Energy is also used to rearrange matter. . | CHAPTER 6 AN INTRODUCTION TO METABOLISM Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section A: Metabolism, Energy, and Life 1. The chemistry of life is organized into metabolic pathways 2. Organisms transform energy 3. The energy transformations of life are subject to two laws of thermodynamics 4. Organisms live at the expense of free energy 5. ATP powers cellular work by coupling exergonic reactions to endergonic reactions The totality of an organism’s chemical reactions is called metabolism. A cell’s metabolism is an elaborate road map of the chemical reactions in that cell. Metabolic pathways alter molecules in a series of steps. 1. The chemistry of life is organized into metabolic pathways Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. The inset shows the first two steps in the catabolic pathway that breaks down glucose. Enzymes selectively .
đang nạp các trang xem trước
