lOMoARcPSD|52942330
Campbell_Biology_Ch_8_Outline_
Summary_University_of_Pennsylvania
, lOMoARcPSD|52942330
Chapter 8: An Introduction to Metabolism
8.1 “An organism’s metabolism transforms matter and energy, subject to the
laws of thermodynamics”
Organization of the Chemistry of Life into Metabolic Pathways
A metabolic process begins with a specific molecule, which then is altered in a
series of defined steps, resulting in a certain product
Each step of the pathway is catalyzed by a specific enzyme
Mechanisms that regulate enzymes balance metabolic supply and demand,
averting deficits or surpluses of important cellular molecules
A major pathway of catabolism is cellular respiration, in which sugar glucose and
other organic fuels are broken down in the presence of oxygen to carbon dioxide
and water
Forms of Energy
Energy is the capacity to cause change
Energy is important because some forms of energy can be used to do work—that is,
to move matter against opposing forces, such as gravity and friction
The forms of energy are kinetic, thermal (heat), potential, chemical energy
The Laws of Energy Transformation
The study of the energy transformations that occur in a collection of matter is
called thermodynamics
There are two laws of thermodynamics
8.2 “The free-energy change of a reactions tells us whether the reaction
occurs spontaneously”
Campbell_Biology_Ch_8_Outline_
Summary_University_of_Pennsylvania
, lOMoARcPSD|52942330
Chapter 8: An Introduction to Metabolism
8.1 “An organism’s metabolism transforms matter and energy, subject to the
laws of thermodynamics”
Organization of the Chemistry of Life into Metabolic Pathways
A metabolic process begins with a specific molecule, which then is altered in a
series of defined steps, resulting in a certain product
Each step of the pathway is catalyzed by a specific enzyme
Mechanisms that regulate enzymes balance metabolic supply and demand,
averting deficits or surpluses of important cellular molecules
A major pathway of catabolism is cellular respiration, in which sugar glucose and
other organic fuels are broken down in the presence of oxygen to carbon dioxide
and water
Forms of Energy
Energy is the capacity to cause change
Energy is important because some forms of energy can be used to do work—that is,
to move matter against opposing forces, such as gravity and friction
The forms of energy are kinetic, thermal (heat), potential, chemical energy
The Laws of Energy Transformation
The study of the energy transformations that occur in a collection of matter is
called thermodynamics
There are two laws of thermodynamics
8.2 “The free-energy change of a reactions tells us whether the reaction
occurs spontaneously”
