Chapter 20- Enzymes And Vitamins

Question 1

Active site

Answer 1

A pocket in a part of the tertiary enzyme structure that binds substrate and catalyzes a reaction

Question 2

Activity

Answer 2

The rate at which an anyone catalyzes the reaction that converts substrate to product

Question 3

Allosteric enzyme

Answer 3

An enzyme that regulates the rate of a reaction when a regulator molecule attaches to a site other than an active site

Question 4

Antibiotics

Answer 4

Substances usually produced by bacteria, mold, or yeast that inhibit growth of bacteria

Question 5

Coenzyme

Answer 5

An organic molecule, usually a vitamin, required as a cofactors in enzyme action

Question 6

Cofactors

Answer 6

A metal ion or an organic molecule that is necessary for a biologically functional enzyme

Question 7

Competitive inhibitor

Answer 7

A molecule with a structure similar to the substrate that inhibits enzyme action by competing for the active site

Question 8

Enzyme

Answer 8

Globular proteins, sometimes with cofactors, that catalyze biological reactions

Question 9

Enzyme substrate (ES) complex

Answer 9

An intermediate consisting of an enzyme that binds tonal substrate in an enzyme- catalyzes reaction

Question 10

Fat-soluble vitamins

Answer 10

Vitamins that are not soluble in water and can be stored in the liver and body fat

Question 11

Feedback control

Answer 11

A type of inhibition in which an end product inhibits the first enzyme in a sequence of enzyme- catalyzes reactions

Question 12

Induced fit model

Answer 12

A model of enzyme action in which the shape of a substrate and the active site of the enzyme adjust to give an optimal fit

Question 13

Inhibitors

Answer 13

Substances that make an enzyme inactive by interfering with its ability to react with a substrate

Question 14

Irreversible inhibition

Answer 14

The loss of enzymatic activity that cannot be reversed

Question 15

Lock and key model

Answer 15

A model of enzyme action in which the substrate is like a key that fits the specific shape of the active site

Question 16

Noncompetitive inhibitor

Answer 16

A type of inhibitor that alters the shape of an enzyme as well as the active site so that the substrate cannot bind properly

Question 17

Optimum pH

Answer 17

The pH at which an enzyme is most active

Question 18

Optimum temperature

Answer 18

The temperature at which an enzyme is most active

Question 19

Reversible inhibition

Answer 19

The loss of enzymatic activity by an inhibitor whose effect can be reversed

Question 20

Simple enzyme

Answer 20

An enzyme that is active as a polypeptide onl

Question 21

Substrate

Answer 21

The molecule that reacts in the active site in an enzyme catalyzes reaction

Question 22

Vitamins

Answer 22

Organic molecules that are essential for a normal health and growth and are obtained in small amounts from the diet

Question 23

Water-soluble vitamins

Answer 23

Vitamins that are soluble in water; they cannot be stored in the body, are easily destroyed by heat, ultraviolet light, and oxygen, and function as coenzymes

Question 24

Zygotes

Answer 24

An inactive form of an enzyme that is activated by the removal of a peptide portion from one end of the protein