Enzymes

Question 1

Large molecules that increase the rates of chemical reactions without themselves undergoing any change.

Answer 1

Enzymes

Question 2

What does an enzyme do?

Answer 2

Provides an alternative pathway (shortcut) through lowering the activation energy

Question 3

What name is given to the non-protein organic portion of an enzyme?

Answer 3

Coenzymes

Question 4

What are the most used cofactors for enzymes?

Answer 4

metallic ions (zinc and magnesium)

Question 5

What name is given to any non-protein portion of an enzyme that is metallic ions?

Answer 5

Cofactor

Question 6

A protein portion of an enzyme that has cofactors or prosthetic groups.

Answer 6

Apoenzyme

Question 7

What is the name given to a material which slows down enzyme function?

Answer 7

Inhibitor

Question 8

What is the inhibitor that binds to the active site and prevents the binding of the substrate?

Answer 8

Competitive inhibitors

Question 9

What is the inhibitor that binds to the active site and changes the shape of the active site?

Answer 9

Noncompetitive inhibitors

Question 10

Where do non-competitive inhibitors bind?

Answer 10

Allosteric site

Question 11

Where does the naming of enzymes base?

Answer 11

1. On the reaction they catalyze

2. On the compound on which they act

Question 12

How can you reverse the effect of competitive inhibitors?

Answer 12

By increasing the substrate concentration

Question 13

What group of enzymes catalyze the removal of H2?

Answer 13

Oxidoreductases

Question 14

What group of enzymes catalyze the transfer of a group of atoms?

Answer 14

Transferases

Question 15

What group of enzymes catalyze the addition of H2O?

Answer 15

Hydrolases

Question 16

What group of enzymes catalyze the joining of two molecules?

Answer 16

Ligases

Question 17

What will cause the rate of enzyme activity to first increase and then level off or plateau?

Answer 17

By increasing the substrate concentration

Question 18

What will cause the rate of enzyme activity to increase linearly without plateau?

Answer 18

By increasing the enzyme concentration

Question 19

They are different forms of the same enzyme found in different tissues but used in the same reaction.

Answer 19

Isozymes

Question 20

Aspartate transaminase transfers the amino group (NH3+) of aspartate to alpha-ketoglutarate. Which group does the enzyme belong to?

Answer 20

Transferase

Question 21

What name is given to the binding of a substrate to an enzyme?

Answer 21

enzyme-substrate complex

Question 22

What is the range of the pH at which the enzyme exhibits maximum activity?

Answer 22

7.0-7.5 pH

Question 23

What do you call the limitation of an enzyme to catalyze specific reactions with specific substrates?

Answer 23

Substrate specificity

Question 24

This type of enzymatic action where the substrate and enzyme do not exactly fit. Thus, the active site changes conformation/shape to allow binding.

Answer 24

induced-fit model

Question 25

The simplest enzyme model that explains the specificity of enzyme action by comparing the active site to a lock and a substrate to a key.

Answer 25

lock-and-key model

Question 26

an antibody with a catalytic ability (enzyme)

Answer 26

abzyme

Question 27

What is the general name used when the product of a reaction sequence inhibits the enzyme in the earlier step as a part of regulation?

Answer 27

Feedback control

Question 28

An enzyme regulation that occurs at a site other than the active site.

Answer 28

Allosterism

Question 29

True or False.

Transition-state analogs mimic the transition states of a substrate.

Answer 29

True

Question 30

What do transition-state analogs do?

Answer 30

They inhibit enzyme activity.