Question 1

The optimum temperature for most enzymes is in the range of ____.

Accepted Answer

A)  25-40S1U1P1$\circ$S1S1P0C 
B)  0-25S1U1P1$\circ$S1S1P0C 
C)  50-70S1U1P1$\circ$S1S1P0C 
D)  40-60S1U1P1$\circ$S1S1P0C 
A)  25-40S1U1P1$\circ$S1S1P0C 
B)  0-25S1U1P1$\circ$S1S1P0C 
C)  50-70S1U1P1$\circ$S1S1P0C 
D)  40-60S1U1P1$\circ$S1S1P0C

Question 2

Cofactors and enzymes form a tightly bound complex without which enzymes will not function.

Accepted Answer

A) True 
 B)False

Question 3

Insulin is initially produced as proinsulin,an inactive form that contains extra amino acid residues.Proinsulin must be an apoenzyme.

Accepted Answer

A) True 
 B)False

Question 4

The synthesis of an enzyme in response to a cellular need is called

Accepted Answer

A)  allosteric production. 
B)  enzyme induction. 
C)  feedback control. 
D)  biofeedback. 
A)  allosteric production. 
B)  enzyme induction. 
C)  feedback control. 
D)  biofeedback.

Question 5

Substrate concentration has what effect on the rate of an enzyme catalyzed reaction?

Accepted Answer

A)  increases 
B)  decreases 
C)  no effect 
D)  increases until reaching a maximum 
A)  increases 
B)  decreases 
C)  no effect 
D)  increases until reaching a maximum

Question 6

The measurement of various enzymes in the blood have been found to be useful for diagnosing pathological conditions.Which of the following enzymes is used to detect bone disease?

Accepted Answer

A)  creatine kinase 
B)  aspartate transaminase 
C)  lactate dehydrogenase 
D)  alkaline phosphatase 
A)  creatine kinase 
B)  aspartate transaminase 
C)  lactate dehydrogenase 
D)  alkaline phosphatase

Question 7

Which of the following is a (are)zymogen(s)?

Accepted Answer

A)  pepsin 
B)  chymotrypsinogen 
C)  carboxypeptidase 
D)  all are zymogens 
A)  pepsin 
B)  chymotrypsinogen 
C)  carboxypeptidase 
D)  all are zymogens

Question 8

Many drugs act as competitive inhibitors.

Accepted Answer

A) True 
 B)False

Question 9

Enzyme assays are reported in international units (IU).By the definition of an IU,the quantity of enzyme present is measured,not the chemical activity.

Accepted Answer

A) True 
 B)False

Question 10

Feedback inhibition is a type of allosteric regulation.

Accepted Answer

A) True 
 B)False

Question 11

The turnover number represents the enzyme concentration.

Accepted Answer

A) True 
 B)False

Question 12

A substance that when added to a reaction causes the production of more product is called a _____ .

Accepted Answer

A)  catalyst 
B)  substrate 
C)  inhibitor 
D)  none of the choices 
A)  catalyst 
B)  substrate 
C)  inhibitor 
D)  none of the choices

Question 13

The cyanide ion is very toxic to humans because it binds with iron (Fe3+)in what enzyme to form a stable complex that stops cellular respiration.

Accepted Answer

A)  cytochrome reductase 
B)  cytochrome kinase 
C)  cytochrome oxidase 
D)  elastase 
A)  cytochrome reductase 
B)  cytochrome kinase 
C)  cytochrome oxidase 
D)  elastase

Question 14

What is the general effect of increasing the substrate concentration in a reaction?

Accepted Answer

A)  The rate of the reaction will increase significantly. 
B)  The rate of the reaction will increase eventually leveling off. 
C)  The rate of the reaction will decrease significantly. 
D)  The substrate concentration cannot be changed in any chemical reaction. 
A)  The rate of the reaction will increase significantly. 
B)  The rate of the reaction will increase eventually leveling off. 
C)  The rate of the reaction will decrease significantly. 
D)  The substrate concentration cannot be changed in any chemical reaction.

Question 15

Which of the following terms is a general definition of an enzyme?

Accepted Answer

A)  catalyst 
B)  lipid 
C)  carbohydrate 
D)  activator 
A)  catalyst 
B)  lipid 
C)  carbohydrate 
D)  activator

Question 16

Enzymes which are affected by the binding of modulators are called

Accepted Answer

A)  induced enzymes. 
B)  proenzymes. 
C)  allosteric enzymes. 
D)  controlled enzymes. 
A)  induced enzymes. 
B)  proenzymes. 
C)  allosteric enzymes. 
D)  controlled enzymes.

Question 17

An enzyme name of maltase indicates that the substrate is a carbohydrate.

Accepted Answer

A) True 
 B)False

Question 18

Under saturation conditions,an enzyme-catalyzed reaction had a velocity V.Which of the following would increase the rate of the reaction?

Accepted Answer

A)  a decrease in the substrate concentration 
B)  an increase in the substrate concentration 
C)  a decrease in the enzyme concentration 
D)  an increase in the enzyme concentration 
A)  a decrease in the substrate concentration 
B)  an increase in the substrate concentration 
C)  a decrease in the enzyme concentration 
D)  an increase in the enzyme concentration

Question 19

Sulfa drugs prevent bacterial growth by acting as ____ inhibitors.

Accepted Answer

A)  competitive 
B)  noncompetitive 
C)  irreversible 
D)  more than one response is correct 
A)  competitive 
B)  noncompetitive 
C)  irreversible 
D)  more than one response is correct

Question 20

Which of the following describes the significance of the term Vmax ?

Accepted Answer

A)  how rapidly a substrate molecule can travel to an enzyme 
B)  the maximum rate that an enzyme can process substrate species 
C)  the velocity at which the enzyme and substrate must collide for activation 
D)  the maximum speed at which product molecules leave the binding site. 
A)  how rapidly a substrate molecule can travel to an enzyme 
B)  the maximum rate that an enzyme can process substrate species 
C)  the velocity at which the enzyme and substrate must collide for activation 
D)  the maximum speed at which product molecules leave the binding site.

Exam 20: Enzymes

The optimum temperature for most enzymes is in the range of ____.

Cofactors and enzymes form a tightly bound complex without which enzymes will not function.

Insulin is initially produced as proinsulin,an inactive form that contains extra amino acid residues.Proinsulin must be an apoenzyme.

The synthesis of an enzyme in response to a cellular need is called

Substrate concentration has what effect on the rate of an enzyme catalyzed reaction?

The measurement of various enzymes in the blood have been found to be useful for diagnosing pathological conditions.Which of the following enzymes is used to detect bone disease?

Which of the following is a (are)zymogen(s)?

Many drugs act as competitive inhibitors.

Enzyme assays are reported in international units (IU).By the definition of an IU,the quantity of enzyme present is measured,not the chemical activity.

Feedback inhibition is a type of allosteric regulation.

The turnover number represents the enzyme concentration.

A substance that when added to a reaction causes the production of more product is called a _____ .

The cyanide ion is very toxic to humans because it binds with iron (Fe3+)in what enzyme to form a stable complex that stops cellular respiration.

What is the general effect of increasing the substrate concentration in a reaction?

Which of the following terms is a general definition of an enzyme?

Enzymes which are affected by the binding of modulators are called

An enzyme name of maltase indicates that the substrate is a carbohydrate.

Under saturation conditions,an enzyme-catalyzed reaction had a velocity V.Which of the following would increase the rate of the reaction?

Sulfa drugs prevent bacterial growth by acting as ____ inhibitors.

Which of the following describes the significance of the term Vmax ?

Matter, measurements, and Calculations

Atoms and Molecules

Electronic Structure and the Periodic Law

Forces Between Particles

Chemical Reactions

The States of Matter

Solutions and Colloids

Reaction Rates and Equilibrium

Acids,bases,and Salts

Radioactivity and Nuclear Processes

Organic Compounds: Alkanes

Unsaturated Hydrocarbons

Alcohols, phenols, and Ethers

Aldehydes and Ketones

Carboxylic Acids and Esters

Amines and Amides

Carbohydrates

Lipids

Proteins

Nucleic Acids and Protein Synthesis

Nutrition and Energy for Life

Carbohydrate Metabolism

Lipid and Amino Acid Metabolism

Body Fluids

Filters

The cyanide ion is very toxic to humans because it binds with iron (Fe³⁺)in what enzyme to form a stable complex that stops cellular respiration.

Which of the following describes the significance of the term V_max ?