Lactate Dehydrogenase (LDH)

Question 1

LDH
An oxidoreductase that catalyzes the interconversion of—- and —— acids

A. Lactic and monohydrate acid
B. Lactate and pyruvic acid

Answer 1

B. Lactate and pyruvic acid

Question 2

LDH is Widely distributed, and has highest activities in——

A. heart
b. hepatic
c. skeletal muscle
D. RBC
E. All

Answer 2

E. All

Question 3

hydrogen transfer enzyme

A. Ast
B.ldh
C. Pyruvic
D. Lactate

Answer 3

B.ldh

Question 4

Lactate Dehydrogenase (LDH) molecule structure?

Answer 4

Tetrameric molecule

Question 5

Composed of 4 monomers; 2 possible active subunits: H & M)

A. Tetrameric ldh
B. Monomeric ldh

Answer 5

A. Tetrameric ldh

Question 6

How many isoenzymes has LDH HAS

Answer 6

5 isoenzymes

Question 7

T OR FALSE
Storage of the sample does not affect the activity of the LD

Answer 7

False it affect

Question 8

LDH

SERUM OR PLASMA FROZEN (low) storage will ——— activity.

A. Increase
B. Decrease

Answer 8

B. Decrease

Question 9

LDH SAMPLE should be stored at RT up to —— days

Answer 9

2 days

Question 10

Chemical reaction product of LDH

A. Pyruvate+NADH+ H
B. Pyruvate+NAD+ H

Answer 10

A. Pyruvate+NADH+ H

Question 11

Most commonly used method because it produces a positive rate,
✓ This method is not affected by product inhibition

A. Wacker Method
B. Wrobleuski La Due

Answer 11

A. Wacker Method

Question 12

wacker method in LDH
—— in absorbance is monitored at ——— nm

A. Increase,200nm
B.decrease 490nm
C.increase 340nm
D.decrease500nm

Answer 12

C.increase 340nm

Question 13

WACKER METHOD

Optimal pH ——-

A. 8.3-8.5
B. 8.3-8.9

Answer 13

B. 8.3-8.9

Question 14

(Lactate- Pyruvate)

A. Wacker Method
B. Wrobleuski La Due

Answer 14

A. Wacker Method

Question 15

Reverse Reaction (Pyruvate- Lactate)

A. Wacker Method
B. Wrobleuski La Due

Answer 15

B. Wrobleuski La Due

Question 16

Wrobleuski La Due method in LDH
—— in absorbance is monitored at —— nm

A. Decrease 320nm
B.increase 340nm
C. Decrease 340nm

Answer 16

C. Decrease 340nm

Question 17

Three times faster but more susceptible to substrate exhaustion

A. Macro ck
B. Pyruvate
C. Tanzer
D. Wrobleuski La Due

Answer 17

D. Wrobleuski La Due

Question 18

Wrobleuski La Due in LDH

Optimal pH is ——

A. 8.3-8.9
B. 7.1-7.4

Answer 18

B. 7.1-7.4

Question 19

Has greater affinity to H subunits

A. (α-HBD)
B. β-glycerophosphate

Answer 19

A. (α-HBD)

Question 20

α-hydroxybutyrate dehydrogenase reaction product

A. a-hydroxybutyrate+ NAD
B. a-hydroxybutyrate

Answer 20

B. a-hydroxybutyrate

Question 21

Represents the LDH-1, 4subunits

A.α-hydroxybutyrate dehydrogenase
B. Alkaline Orthophosphoric Monoester Phosphohydrolase

Answer 21

A.α-hydroxybutyrate dehydrogenase

Question 22

After MI, LD begin to rise within ______

A. 10-24 hours
B.48-72 hours

Answer 22

A. 10-24 hours

Question 23

LD IN MI, remains elevated for how many days.

a. 10 days
b. 5 days
c. 2 days

Answer 23

a. 10 days

Question 24

3 Test used to diagnose AMI

Answer 24

CK-MB
CARDIAC TROPININ (I,T)
CRP

“3C”