Chapter 13 - Enzymes

Question 1

Enzyme portion

Answer 1

Apoenzyme

Question 2

Digestive enzymes in structurally inactive form

Answer 2

Proenzyme/zymogen

Question 3

Trypsin

Answer 3

Hydrolases

Question 4

Water-free cavity, where the substance on which the enzyme acts interacts with particularly charged amino acid residues

Answer 4

Active site

Question 5

Chymotrypsin

Answer 5

Hydrolases

Question 6

alpha-amylase

Answer 6

Hydrolases

Question 7

Creatinine kinase

Answer 7

Transferases

Question 8

Enzymes contains a specific amino acid sequence

Answer 8

Primary structure

Question 9

Aldolase

Answer 9

Lyases

Question 10

Polypeptide chains twisting

Answer 10

Secondary structure

Question 10

Organic cofactor

Answer 10

Coenzyme (NAD)

Question 11

5-nucleotidase

Answer 11

Hydrolases

Question 12

Cholinesterase

Answer 12

Hydrolases

Question 13

Inorganic cofactors, also called activators

Answer 13

Chloride or magnesium ions

Question 15

May bind regulator molecules and, thereby, be significant to the basic enzyme structure

Answer 15

Allosteric site

Question 16

Elastase-1

Answer 16

Hyrolases

Question 17

Glutathione synthetase

Answer 17

Ligase

Question 18

Folds —> structural cavities

Answer 18

Tertiary structure

Question 19

Catalyze the joining of two substrate molecules, coupled with breaking of the pyrophosphate bond in ATP or a similar compound

Answer 19

Isomerases

Question 20

Catalyze the interconversion of geometric, optical, or positional isomers

Answer 20

Isomerases

Question 21

Catalyze the transfer of a group other than hydrogen from one substrate to another

Answer 21

Transferases

Question 22

More than one polypeptide unit, refers to the spatial relationships between the subunits

Answer 22

Quaternary structure

Question 24

Pyruvate kinase

Answer 24

Transferases

Question 24

Triacylglycerol lipase

Answer 24

Hydrolases

Question 25

Cataylze hydrolysis of various bonds

Answer 25

Hydrolases

Question 26

Complete and active system

Answer 26

Holoenzyme

Question 27

Catalyze removal of groups from substrates without hydrolysis; the product containing double bonds

Answer 27

Lyases

Question 28

Enzyme is subject to posttransitional modification

Answer 28

Isoform

Question 30

Enzyme exist in different forms within the same individual

Answer 30

Isoenzyme

Question 31

Glycogen phosphorylase

Answer 31

Transferases

Question 32

Nonprotein molecule, necessary for enzyme activity

Answer 32

Cofactor

Question 32

Coenzyme bound tightly to the enzyme

Answer 32

Prosthetic group

Question 33

Catalyze an oxidation-reduction reaction between two substrates

Answer 33

Oxidoreductases

Question 34

Enzymes combines with only one substrate

Answer 34

Absolute specificity

Question 35

They combine with all substrates containing a particular chemical group (phosphate ester)

Answer 35

Group specific

Question 36

Enzymes are specific to chemical bonds

Answer 36

Bond specificity

Question 37

Enzymes that predominantly combine with only one optical isomer of a certain compound

Answer 37

Stereoisometric specificity

Question 38

A physical binding of a substrate to the active site of an enzyme

Answer 38

ES complex

Question 39

The substrate readily binds to free enzyme at a low concentration

Answer 39

Substrate concentration

Question 40

The higher the enzyme level, the faster the reaction will proceed because more enzyme is present to bind with substrate

Answer 40

Enzyme concentration

Question 41

Changes in pH may denature an enzyme or influence its ionic state, pH range 7.0 - 8.0

Answer 41

pH

Question 42

Increase temperature —> Increase the rate of a chemical reaction Usually at 40C

Answer 42

Temperature

Question 43

Metallic Activators

Answer 43

Ca2+, Fe2+, Mg2+, Mn2+, Zn2+, K+

Question 44

Nonmetallic activators

Answer 44

Br-, Cl-

Question 45

Common coenzymes

Answer 45

Nucleotide phosphates and vitamins

Question 46

Increasing coenzyme concentration will increase the velocity of an enzymatic reaction in a manner synonymous with increasing substrate concentration

Answer 46

Cofactors

Question 47

Interferes with the reaction

Answer 47

Inhibitors

Question 48

Physically bind to the active site for an enzyme, and compete with the substrate for the active site Inhibitors are reversible

Answer 48

Competitive inhibitors

Question 49

Binds an enzyme at a place other than the active, maybe reversible and irreversible

Answer 49

Noncompetitive inhibitor

Question 50

Inhibitors binds to this ES-complex

Answer 50

Uncompetitive inhibition

Question 51

Acid phosphatase 1) Optimal pH 2) Tissue source 3) Diagnostic significance 4) Most specific substrate 5) Inhibitor 6) Preferred for continuous-monitoring mtds 7) Reference range: Prostatic ACP Tartrate-resistant ACP, adults Children

Answer 51

1) 5.0 pH 2) Prostate, bone, liver, spleen, kidney, erythrocytes, and platelets 3) Prostatic carcinoma, Forensic CC(rape cases), Paget’s dse, breast cancer with bine metastases, Gaucher’s dse 4) Thymolphthalein monophosphate (Roy & Hillman) 5) L-tartrate, formaldehyde and cupric ions (RBC) 6) alpha-naphthyl phosphate, 13abson reading and philipps 7) 0-3.5 mg/dL 1. 5-4.5 U/L (37C) 3. 5-9.0 U/L (37C)

Question 52

Alkaline phosphatase 1) Optimal pH 2) Activator 3) Tissue Source 4) Diagnostic significance 5) Continues-monitoring technique 6) Sources of error 7) Most heat labile inhibited by phenylalanine 8) Inhibited by phenylalanine and leucine

Answer 52

1) 9.0-10.0 pH 2) Mg2+ 3) Liver, bone, intestine, spleen, placenta, kidney 4) Hepatobiliary and bone disorders, Obstructive jaundice, Paget’s dse(osteotic neoformans) 5) Bowers and McComb (p-nitrophenol-yellow) at 405 nm 6) Hemolysis Increases 3-10% on standing 25C/4C for several hrs 7) Regan 8) Nagao