ENZYMES

Question 1

(requires ATP)

Answer 1

synthetase

Question 2

(no ATP required)

Answer 2

synthase

Question 3

(uses water to remove phosphoryl group)

Answer 3

phosphatase

Question 4

(uses Pi to break a bond and generate a phosphorylated product)

Answer 4

phosphorylase

Question 5

catalyzes removal of H+ ions

Answer 5

dehydogenase

Question 6

(O2 is the acceptor, and oxygen atoms are not incorporated into substrate)

Answer 6

oxidase

Question 7

(one or both oxygen atoms are incorporated)

Answer 7

oxygenase

Question 8

is a complete enzyme that consists of an apoenzyme and a cofactor.

Answer 8

Holoenzyme

Question 9

is the protein part of the enzyme

is the protein part of an enzyme that is inactive without its cofactor.

Answer 9

apoenzyme

Question 10

is the non-protein part.

is essential for the enzyme to function.

Answer 10

cofactor

Question 11

is a type of cofactor that is an organic molecule.

typically tightly bound to the apoenzyme, but they can be released from the apoenzyme after the reaction is complete

Answer 11

Coenzyme

Question 12

proposed a simple model that accounts for most of the features of enzyme-catalyzed reactions.

Answer 12

Leonor Michaelis and Maude Menten

Question 13

In this model, the enzyme reversibly combines with its substrate to form an ES complex that subsequently yields a product, regenerating the free enzyme.

Answer 13

Reaction model

Question 14

describes the relationship between the rate of an enzyme-catalyzed reaction and the concentration of the substrate.

Answer 14

Michaelis-Menten equation

Question 15

is characteristic of an enzyme and its particular substrate and reflects the affinity of the enzyme for that substrate.

Answer 15

Km, the Michaelis constant

Question 16

are regulated by molecules called effectors that bind noncovalently at a site other than the active site.

Answer 16

Allosteric enzymes

Question 17

effectors that inhibit enzyme activity

Answer 17

Negative effectors

Question 18

increase enzyme activity

Answer 18

Positive effectors

Question 19

is when the substrate itself serves as an effector.
They bind to the allosteric site of the enzyme and change its shape, which can either activate or inhibit the enzyme.

Answer 19

Homotropic effectors:

Question 20

not the same chemical identity as the enzyme’s substrate.

Answer 20

Heterotropic effectors:

Question 21

is the process of increasing the synthesis of an enzyme. This is usually done in response to a signal molecule, such as a hormone or a nutrient

Answer 21

Induction

Question 22

is the process of decreasing the synthesis of an enzyme. This is usually done when the cell does not need the enzyme.

Answer 22

Repression

Question 23

is abundant in the liver.

Answer 23

ALT