Ap bio - enzymes

All of the chemical reactions in an organism

Series of chemical reactions that either build complex molecules or break up

Releases energy, breaks down complex molecules into simple compounds

Consumes energy, builds complex compounds

Ability to do work

Survive and function

Energy associated w motion

Energy associated w the movement of atoms or molecules

Stored energy

Potential energy available for release in a chemical reaction

Thermodynamics (does not describe the rate of the reaction); law applies to the universe as a whole

Energy cannot be created nor destroyed

Energy transformation increases the entropy (disorder) of the universe

To determine the likelihood of reactions in organisms, or if the reactions are energetically favorable

Spontaneously

Exergonic or endergonic

Releases energy, ex. Cellular rep G<O

Absorbs free energy, ex. Photosynthesis

True

Movement; cilia movement of chromosomes, contraction of muscles

Pumping substances across membranes AGAINST SPONTANEOUS MOVEMENT

Synthesis of molecules (ex. Building polymers from monomers)

Molecules that organisms use as a source of energy to perform work

ATP couples Exergonic reactions to endergonic reactions to power CELLULAR WORK (Exergonic process drives endergonic process

By breaking the bond between the 2nd and 3rd phosphate in a hydrolysis reaction

The released phosphate moves to another molecules to give energy

Comes from the lowering of free energy NOT from the bond itself

ADP can be regenerated to ATP via the ATP cycle

Macrocolecules that catalyze reactions by lowering activation evergy

Substrates are held in active site by WEAK INTERACTIONS

Enzymes will change the shape of their active site to allow the substance to bind better

Temp, pH, chemicals

Being outside the normal pH range can cause hydrogen bonds in the enzyme to break, changing the shape of the enzyme

Non protein molecules that assist in enzyme function

Consist of metals

An enzyme with the cofactor attached

Organic cofactors

Reduce the activity of specific enzymes

Inhibitor binds w covalent bonds ex. Toxins and poisons

Inhibitor binds w weak interactions

Reduce enzyme activity by blocking substrates from binding to the active site, inhibition can be reversed w increased substrates concentrations

Bind to an area other than the active site (allosteric site), which changes the shape of the active site which prevents substrates from binding

Controlling where and where enzymes are active and switching genes that code for enzymes on or off

Molecules bind (non covalent interactions) to an allosteric site which changes the shape and function of the active site

Inhibition or stimulation (by an activator) of the enzymes activity

Substrate binds to allosteric site and stabilizes the shape of the enzyme so that the active sites remains open

Substrate binds to allosteric site and stabilizes the enzyme shape so that the active sites are closed

Substrate binds to one active site (on an enzyme with more than one active site) which stabilizes the active form

The end product of a metabolic pathway can act as an inhibitor to an early enzyme in the same pathway