Energy and enzymes

metabolism

sum of all the chemical reactions occurring within a cell or organism

metabolic pathway

series of chemical reactions in which the products of one reaction become the reactions of the following reaction

heat

thermal energy of a sample

activation energy

Energy needed to get a reaction started

active site

a region on an enzyme that binds to a protein or other substance during a reaction.

allosteric regulation

The binding of a regulatory molecule to a protein at one site that affects the function of the protein at a different site.

ATP (adenosine triphosphate)

energy currency of the cell

denaturation

loss of normal shape of a protein due to heat/pH or other factor

endergonic

A chemical reaction that requires the input of energy in order to proceed.

energy

capacity to do work; stored in the forms of chemical bonds (potential energy)

enzyme

A type of protein that speeds up a chemical reaction in a living thing

enzyme-substrate complex

complex structure created while an enzyme is acting on its substrate to create the products of a chemical reaction; held together by weak chemical interactions

inhibitor

substance that binds to an enzyme, preventing it from binding to its substrate and decreasing the activity of the enzyme; can be competitive or non-competitive

exergonic

Chemical reactions that release energy

substrate

A specific reactant acted upon by an enzyme

1st Law of Thermodynamics

energy cannot be created or destroyed, only transformed from one type to another

2nd Law of Thermodynamics

Every energy transfer or transformation increases the entropy of the universe. (entropy - measure of disorder)

Gibbs Free Energy

the amount of energy in a system available to do work; spontaneous = negative free energy (exergonic); nonspontaneous = positive free energy (endergonic)