Chapter 7
Metabolism
Metabolism represents all of the chemical activity in a cell, including reactions that build molecules (anabolism) and those that break molecules…
The First Law of Thermodynamics states that energy cannot be created or destroyed, only transformed. This can be demonstrated within a classic food…
The Second Law of Thermodynamics states that entropy, or the amount of disorder in a system, increases each time energy is transferred or…
Kinetic energy is the ability of an object in motion to do work or enact change. It can take on many forms. For instance, water flowing down a…
Potential energy is a stored form of energy that has the potential to do work, and therefore, to be converted into kinetic energy. Gravitational…
Free energy—abbreviated as G for the scientist Gibbs who discovered it—is a measurement of useful energy that can be extracted from a…
Activation energy is the minimum amount of energy necessary for a chemical reaction to move forward. The higher the activation energy, the slower the…
The bonds of adenosine triphosphate (ATP) can be broken through the addition of water, releasing one or two phosphate groups in an exergonic process…
The addition or removal of phosphate groups from proteins is the most common chemical modification that regulates cellular processes. These…
Most chemical reactions in cells require enzymes—biological catalysts that speed up the reaction without being used up or permanently changed.…
Enzymes speed up reactions by lowering the activation energy of the reactants. The speed at which the enzyme turns reactants into products is called…
Inhibitors are molecules that reduce enzyme activity by binding to the enzyme. In a normally functioning cell, enzymes are regulated by a variety of…
Biochemical reactions are occurring constantly in cells, converting starting substances to different products, usually with the help of enzymes that…
Allosteric regulation of enzymes occurs when the binding of a molecule to a different location from the active site causes a change in enzymatic…
Enzymes require additional components for proper function. There are two such classes of molecules: cofactors and coenzymes. Cofactors are metallic…
Obesity represents the most important single risk factor in the pathogenesis of type 2 diabetes, a disease which is characterized by a resistance to…
Monocytes are innate immune cells that can be activated by pathogens and inflammation associated with certain chronic inflammatory diseases.…
Skeletal muscle is the largest glucose deposit in mammals and largely contributes to glucose homeostasis. Assessment of insulin sensitivity of muscle…
