chempath tut3

1.1 Which of the following describes the chemical characteristic of an antibody?
a. carbohydrate
b. lipid
c. protein
d. electrolyte
e. ligand

1.2 Immunonephelometry is based upon the principle that :
a. antigen and antibody form complexes in antigen excess
b. antigen and antibody react to form precipitin line
c. antigen and antibody form small complexes in antibody excess
d. antigen and antibody form large complexes which precipitate
e. antigen and antibody form large lattice structures, which precipitate.

1.3 In double diffusion, immune precipitation reactions occur when two lines cross each other: the reaction is one of:
a. antigen identity
b. identity
c. partial identity
d. antibody identity
e. non – identity

1.4 Which of the following factors affects antigenicity?
a. chemical nature
b. size
c. conformation
d. genetics
e. all are correct

1.5 Laurell ‘ rocket’ immunoelectrophoresis requires :
a. agarose
b. purified antigen
c. ac power supply
d. agarose mixed with antibody
e. none are correct
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1.6 Which of the following compounds are not often monitored by competitive binding assays?
a. therapeutic drugs
b. protein hormones
c. estrogens
d. electrolytes
e. antibiotics


1.7 How much CaSO4 (Ca = 40; S = 32; O = 16) should be weighed to prepare one litre of a 0.5 M solution of CaSO4?:

a. 6.8 g
b. 13 g
c. 27.2 g
d. 34 g
e. 68 g

1.8 A tube contains the following:
Serum : 0.25 ml Saline : 0.75 ml Antigen : 1.0 ml
What is the serum dilution?

a. 1:2
b. 1:4
c. 1:7
d. 1:8
e. 1:16

1.9 How many ml of concentrated HCl (specific gravity = 1.2 ; 30 purity) would be needed to prepare one litre of a 4 M solution
( atomic weight H = 1 Cl = 35 )?:

a. 72 ml
b. 86.4 ml
c. 144 ml
d. 200 ml
e. 400 ml


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1.10 A crystal scintillation detector is primarily used for detecting radionuclides emitting:

a. positrons
b. gamma rays
c. negatrons
d. X – rays
e. Ultraviolet light

1.11 125I is used as a label because:

a. it has high specific activity
b. it is a high energy emitter
c. it has a long half-life
d. all of the above
e. none of the above.

[11]

2. Write an essay on the steps involved in the practical performance of RIA. Give a full explanation on each step i.e. reasons where possible. [12]


3. Explain the principle used in RAST technique. [4]

4. Describe 5 of the following immunochemical techniques:
4.1 Radial Immunodiffusion
4.2 Immunoelectrophoresis :
4.3 Isoelectric focusing ( IEF )
4.4 Western blot
4.5 Laurell ‘Rocket’ immunoelectrophoresis
4.6 Immunonephelometry


[10]




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5. Explain all the requirements for labels in immunoassays. [5]


6. Draw a typical RIA graph for which a test like cortisol is plotted.
[2]


7. Discuss how the entry of radioactivity may be prevented. [6]


8. What are the following acronyms (with regard to radioactivity)?:
8.1 R

8.2 RAD

8.3 REM
[3]


9. Write short notes on waste disposal of radioactive material. [7]