proteins and electrophoresis

Question 1

Kjedahl’s procedure, the reference method for protein, for total protein is based upon the premise that:

Answer 1

The nitrogen content of proteins is measure by acid digestion

Question 2

The term biuret reaction refers to

Answer 2

coordinate bonds between Cu++ and carboxyl and amino groups of biuret

Question 3

Hyperalbuminemia is caused by:

Answer 3

Dehydration syndromes

Question 4

High serum total protein with normal albumin is usually seen in:

Answer 4

Multiple myeloma

Question 5

At pH 8.6 proteins are ____________ charged and migrate toward the ______________.

Answer 5

Negatively Anode

Question 6

Electrophoretic movement of proteins toward the anode will be made to decrease by increasing the

Answer 6

Ionic strength of the buffer

Question 7

Which of the conditions below will prevent any migration of proteins across an electrophoretic support medium such as agarose?

Answer 7

Loss of contact between a buffer chamber and the medium

Question 8

Which of the following conditions is associated with “beta-gamma” bridging?

Answer 8

Hepatic cirrhosis

Question 9

Which of the proteins listed below has the highest pI?
Albumin 
  Transferrin 
  Ceruloplasmin 
  IgG

Answer 9

IgG

Question 10

At pH 8.6, the cathodal movement of gamma globulins is caused by:

Answer 10

electroendosomosis

Question 11

Which of the proteins listed below migrates in the beta region at pH 8.6?
Haptoglobin 
  Orosomucoprotein 
  Antitrypsin 
  Transferrin

Answer 11

Transferrin

Question 12

Which of the following abnormal Hgbs migrates to the same position as Hgb S on cellulose acetate or agarose at pH 8.6?

Answer 12

Hgb DPunjab

Question 13

The correct order of Hgb migration on cellulose acetate at pH 8.6:

Answer 13

• C  S  F  A +

Question 14

The correct order of Hgb migration on citrate agar at pH 6.3

Answer 14

• F  A  S  C +

Question 15

Which Hgb migrates to the same position as Hgb C at pH 8.6?

Answer 15

Hgb A2

Question 16

The intensity of the color produced in the biuret reaction is dependent on the number of complexes formed between cupric ions and the peptide bonds of a protein. In order for this reaction to take place, it is necessary that the number of peptide bonds present be at least:

Answer 16

2

Question 17

A glycoprotein that binds with hemoglobin to facilitate the removal of hemoglobin by the reticuloendothelial system is:

Answer 17

Haptoglobin

Question 18

A congenital disorder that is characterized by a split in the albumin band when serum is subjected to electrophoresis is known as:

Answer 18

Bisalbuminemia

Question 19

In a healthy individual the protein fraction with the greatest concentration in serum is:

Answer 19

Albumin

Question 20

Proteins are dipolar or zwitterion compounds containing both positive and negative charges. When a protein is at its isoelectric point, the protein will have a:

Answer 20

Net zero charge

Question 21

Serum protein electrophoresis is routinely performed on the serum obtained from a clotted blood specimen. If a plasma specimen is substituted for serum:

Answer 21

Electrophoresis will show an extra fraction –fibrinogen –in the beta-gamma region

Question 22

In serum protein electrophoresis, when a barbital buffer of pH 8.6 is employed, the protein fraction that migrates the fastest toward the anode is:

Answer 22

albumin

Question 23

When electrophoresis is performed, holes appear in the staining pattern, giving the stained protein band a doughnut-like appearance. What is the probable cause of this problem?

Answer 23

The protein concentration was too high `

Question 24

Which of the following serum protein fractions is most likely to be retained in the plasma of patients with nephrotic syndrome?

Answer 24

alpha-2 globulin

Question 25

Bence Jones proteinuria is a condition characterized by the urinary excretion of:

Answer 25

either kappa or lambda light chains

Question 26

Which total protein method requires alkaline copper sulfate?

Answer 26

Biuret

Question 27

Dye-binding methods are used for the quantitation of albumin in serum without the preliminary extraction of the globulin. An anionic dye that binds selectively with albumin is:

Answer 27

Bromcresol green

Question 28

``` The liver is the primary source of the plasma proteins. All of the following plasma proteins are manufactured by the liver except: Albumin Fibrinogen IgG Transferrin ```

Answer 28

IgG

Question 29

A characteristic of the Bence Jones protein that is used to distinguish it from other urinary proteins is its solubility:

Answer 29

with precipitation at 40C -60C

Question 30

Analysis of CSF for oligoclonal bands is used to screen for which of the following disease states?

Answer 30

multiple sclerosis

Question 31

When performing a manual protein analysis on a xanthochromic spinal fluid, the technologist should:

Answer 31

make a patient blank

Question 32

The normal concentration of proteins in cerebrospinal fluid, relative to serum protein is approximately:

Answer 32

<1%

Question 33

In an electrophoretic separation, the zones appear artifactually crescent-shaped. The most likely cause is:

Answer 33

overload of sample

Question 34

``` Which one of the protein bands, when separated from serum by electrophoresis on cellulose acetate, contains only one protein? Albumin alpha-1-globulin alpha-2-globulin beta globulin ```

Answer 34

Albumin

Question 35

Which protein test is not able to detect immunoglobulin light chains (i.e. Bence Jones proteins) a. Immunofixation electrophoresis (IFE) b. Protein precipitation between 40 and 60C. c. Sulfosalicylic acid (SSA) precipitation test d. Reagent strip test based on the protein error of indicators

Answer 35

d. Reagent strip test based on the protein error of indicators

Question 36

Using the Trichloacetic Acid Method for manual protein in urine, 524 mg/dl were detected in a 24 hour urine with a volume of 1850 ml. What is the 24 hour urine protein?

Answer 36

9.7 g/24 hrs