Biochemistry - Ch 01 - Lecture 1, 2 - Cells And Thermodynamics (Vocab)

Front 1

Define:

Catalyst

Back 1

A substance that promotes a chemical reaction without itself undergoing permanent change. A catalyst increases the rate at which a reaction approaches equilibrium but does *not* affect the free energy change of the reaction.

Front 2

Define:

Closed System

Back 2

A thermodynamically system that can exchange energy but not matter with its surroundings.

Front 3

Define:

Condensation Reaction

Back 3

The formation of a covalent bond between two molecules, during which the elements of water are lost; the reverse of hydrolysis.

Front 4

Define:

Endergonic process

Back 4

A process that has an overall positive free energy change (a nonspontaneous process).

Front 5

Define:

Enzyme

Back 5

A biological catalyst. Most enzymes are proteins; a few are RNA.

Front 6

Define:

Equilibrium

Back 6

The point in a process at which the forward and reverse reaction rates are exactly balanced so that it undergoes no net change.

Front 7

Define:

Equilibrium Constant

Back 7

K_eq

The ratio, at equilibrium, of the product of the concentrations of reaction products to that of its reactants.

K_eq is related to ΔG⁰ for the reaction:
ΔG⁰ = -RT*ln(K_eq)

Usually abbreviated K.

Front 8

Define:

Exergonic process

Back 8

A process that has an overall negative free energy change (a spontaneous process).

Front 9

Define:

Functional Group

Back 9

A portion of a molecule that participates in interactions with other substances. Common functional groups in biochemistry are:

acyl, amido, amino, carbonyl, carboxyl, diphosphoryl (pyrophosphoryl), ester, ether, hydroxyl, imino, phosphoryl, and sulfhydryl...

...groups

Front 10

Define:

Hydrolysis

Back 10

The cleavage of a covalent bond accomplished by adding the elements of water; the reverse of a condensation.

Front 11

Define:

Isolated System

Back 11

A thermodynamic system that cannot exchange matter or energy with its surroundings.

Front 12

Define:

Open System

Back 12

A thermodynamic system that can exchange matter and energy with its surroundings.

Front 13

Define:

Organic Compound

Back 13

A compound that contains the element carbon.

Front 14

Define:

Polymer

Back 14

A polymer consisting of numerous smaller units that are linked together in an organized manner. Polymers may be linear or branched and may contain one or more kinds of structural units (monomers)

Front 15

Define:

Prebiotic Era

Back 15

The period of time between the formation of the earth ~4.6 bya and the appearance of living organisms at least 3.5 bya.

Front 16

Define:

Spontaneous Process

Back 16

A thermodynamic process that occurs without the input of free enregy from outside the system.

Spontaneity is independent of the rate of a process.