Bio 1305 Chapter 8

a catabolic pathway. Cellular respiration is a catabolic pathway.

the covalent bonds of a sugar molecule: potential energy. Bonds are a form of potential energy because the energy arises from the relative positions of the atoms that form the bond.

The entropy of the products is greater than the entropy of the reactants. A large molecule (glucose) has been converted into several smaller molecules (water and carbon dioxide); thus, the products have more disorder (greater entropy) than the reactants.

A reaction that is at equilibrium is not capable of doing any work. The ΔG for a reaction at equilibrium is zero, which means that there is no free energy available to do any work.

The cycling between ATP and ADP + Pi provides an energy coupling between catabolic and anabolic pathways. Catabolic pathways provide the energy needed to make ATP from ADP and Pi. The hydrolysis of ATP to ADP + Pi releases the same amount of energy.

increase the rate of a reaction without being consumed by the reaction. This permits enzyme molecules to be used repeatedly.

The enzyme has an allosteric regulatory site. The allosteric site is distinct from the active site, and does not affect the substrate specificity of the enzyme.

The active site can provide heat from the environment that raises the energy content of the substrate. An enzyme cannot extract heat from the environment to speed a reaction. It can only lower the activation energy barrier so that more substrates have the energy to react.

A competitive inhibitor slows down the enzyme by competing with the substrate for binding at the active site. Increasing substrate concentrations will reduce the effectiveness of a competitive inhibitor.

the final product of the path way controls the overall pathway

increase the enzyme concentration

5

they have a high optimal temperature

nothing

Energy is released from broken bonds -bonds reformed and that's how they release energy down hill reaction ex - ATP to ADP

Consume energy to build things uphill reaction ex - photosynthesis

Kinetic, potential, chemical, thermal

energy of motion

type of kinet energy associated with the random movement of atoms or molecules

energy associated with structure or position

conservation of energy - energy can neither be created nor destroyed, can only be transformed

Entropy is always increasing

utilizes entropy as a mechanism for forward reactions

∆G° = ∆H - T∆S° - ∆G° = free energy - ∆H° = change in the system's enthalpy (total energy) - T = temperature in Kelvin - ∆S° = change in the system's entropy

-∆G

there is no further change in the concentration of products or reactants

-∆G - energy is released - occur spontaneously -

Energy is put into the system -stores energy in molecules

Mechanical Chemical Transport

7.3 kilocalories/mole under ideal conditions

• Using energy to drive something else • Using an exergonic reaction to fuel an endergonic reaction o Process with a negative Delta G that is greater than the positive delta G to make the process spontaneous

decrease the required activation energy

• Active site, cooperativity - enzyme closes around substrate a little more

C - covalently bound O - orienting substrates together P - Providing a favorable environment S - Stress

• Non-protein enzyme helper for catalytic activity • Can be vitamins or metals

• Competitive inhibitor binds at the active site • Noncompetive - binds anywhere away from the active site o Usually changes shape o EX CO2

Allosteric Allo - other Steric - place

o Allo - other o Steric - place o Binds away from the active site and causes some kind of a change Needs to be in order to be allostaric o Can be positive or negative o If something binds to one site then it helps activate the other site

activator

inhibitor

final product of the reactions acts as an inhibitor for a reaction - aka negative feedback reaction

most spontaneous (giving off the most energy)

non-spontaneous (decreasing the entropy)

you want a high temperature (will make it spontaneous)

you want temperature really low to be spontaneous