Mastering Biology HW Chapter 8

c) The products have less potential energy than the reactants.

d) heat has been released to the environment.

a) exergonic; energy has been released

d) exergonic; In exergonic reactions the products have less potential energy than the reactants.

d) endergonic; The products of endergonic reactions have more potential energy than the reactants.

c) ATP (adenosine triphosphate); The hydrolysis of ATP provides the energy needed for an endergonic reaction.

b) endergonic; Energy has been acquired from the surroundings

b) exergonic; The energy released by an exergonic reaction can be used to drive an endergonic reaction.

b) It is acquired by a reactant in an endergonic reaction.; By acquiring the phosphate group the reactant acquires energy.

5) endergonic; The products contain more potential energy than the reactants.

d) exergonic...uphill; exergonic reactions release energy.

e) the use of energy released from an exergonic reaction to drive an endergonic reaction

Order: Uncatalyzed, Enzyme A, Enzyme B *Enzymes lower the activation energy of a chemical reaction. This means that a catalyzed reaction is more likely to proceed than an uncatalyzed reaction, and it forms products more rapidly than an uncatalyzed reaction.

D. Denatured

C. Catalyst

G. Specific

B. Cofactor

F. Complex

A. Active site

E. Subtrate

A substrate binds at an enzyme's active site; the enzyme typically recognizes the specific shape of its substrate. A cofactor, such as an inorganic ion or vitamin, may bind to the enzyme and assist in catalyzing the reaction. The reaction environment must be appropriate for catalysis to proceed. An enzyme will denature, or change its shape and lose its biological activity, at too high a temperature or at a pH outside the enzyme's optimal range.

c) P4 binds E1 and deactivates it.; many enzymatic pathways are regulated by the feedback inhibition model described here. In fact, it is so common that another name for it is end-product inhibition.