Human Physiology, Stuart Ira Fox Chapter 4
Questions and Answers
Enzymes *** biological catalysts that speed up the rate of chemical reactions
Ability of enzymes to lower energy requirement is due to __________ *** structure
Substrate *** the reactant on which an enzyme works
conformation of an enzyme *** highly-ordered 3D shape
T/F: Enzymes act by bringing substrates close together so they can react *** True
Substrates fit into the specifically shaped ________ _______ of the enzymes that
catalyze their reactions. *** active sites
enzyme activity influenced by: *** temperature, pH, concentration of cofactors,
coenzymes, enzyme and substrate
Enzymes have optimal ________ and ________ *** temperature; pH ranges
cofactors and coenzymes *** two types of activators (ways to turn on enzymes);
necessary for normal activity of enzymes
Cofactors *** include metal ions such as Ca, Mg, Mn, Zn, Cu, Se
Coenzymes *** are organic molecules derived from vitamins
T/F: Coenzymes transport small molecules needed by enzymes *** True
zymogen *** inactive form of an enzyme
Rate of product formation increases as ________ increases; (until reaction rate reaches
a plateau) *** substrate concentration
Where enzyme is said to be __________, every enzyme in a solution is being used and
adding anymore substrates will not increase rate of chemical reaction *** saturated
law of mass action *** The rate of a chemical reaction is proportional to the product of
the concentrations of the reactants
Questions and Answers
Enzymes *** biological catalysts that speed up the rate of chemical reactions
Ability of enzymes to lower energy requirement is due to __________ *** structure
Substrate *** the reactant on which an enzyme works
conformation of an enzyme *** highly-ordered 3D shape
T/F: Enzymes act by bringing substrates close together so they can react *** True
Substrates fit into the specifically shaped ________ _______ of the enzymes that
catalyze their reactions. *** active sites
enzyme activity influenced by: *** temperature, pH, concentration of cofactors,
coenzymes, enzyme and substrate
Enzymes have optimal ________ and ________ *** temperature; pH ranges
cofactors and coenzymes *** two types of activators (ways to turn on enzymes);
necessary for normal activity of enzymes
Cofactors *** include metal ions such as Ca, Mg, Mn, Zn, Cu, Se
Coenzymes *** are organic molecules derived from vitamins
T/F: Coenzymes transport small molecules needed by enzymes *** True
zymogen *** inactive form of an enzyme
Rate of product formation increases as ________ increases; (until reaction rate reaches
a plateau) *** substrate concentration
Where enzyme is said to be __________, every enzyme in a solution is being used and
adding anymore substrates will not increase rate of chemical reaction *** saturated
law of mass action *** The rate of a chemical reaction is proportional to the product of
the concentrations of the reactants
