college biology-chapter 6

intermediates

compounds formed between the beginning and end of a metabolic pathway

energy carriers

Mainly ATP; donate energy to reactions

enzymes

proteins (usually) that catalyze reactions

degradative pathway

organic compounds are broken down to release energy (catabolic)

biosynthetic pathway

Complex organic compounds are built from simpler molecules (anabolic)

chemical equilibrium

the rate of the forward reaction is equal to the rate of the reverse reaction

metabolic pathway

an orderly series of reactions catalyzed by enzymes

cyclic pathway

a pathway in which the last step regenerates a reactant molecule used in the first step

entropy

a measure of the disorder of a system / measure of the amount of concentrated energy that has been dispersed in a system

Metabolism

includes all of the activities by which a cell acquires energy and materials and uses them to build, break apart, store, and release substances in controlled processes that are typical for that cell

kilocalorie

the measure of energy that can heat 1,000 grams of water from 14.5C to 15.5C at a standard pressure

chemical energy

the potential energy stored in the attractive forces (bonds) that cause atoms to group together into molecules

heat

also called thermal energy, resulting from collisions among molecules and their surroundings is a kind of kinetic energy

cofactors

small molecules and metal ions that assist enzymes or serve as carriers

transport proteins

membrane-bound substances that adjust concentration gradients in ways that influence the direction of metabolic reactions

reactants (substrates)

substances able to enter into a reaction