NEET Class neet Answered

The information provided seems incomplete. The question should be as follows:

We need to draw blood from a patient and keep it in a test tube for analysis of blood corpuscles and plasma. We are provided with the following types of test tubes. Which of these will you not use for the purpose?

A Test tube containing Calcium bicarbonate.
B Test tube containing Heparin.
C Chilled test tube.
D Test tube containing Sodium oxalate.

 

If the question is as stated above, below is the required solution.

 

Since we are collecting blood from a patient for biochemical assay, we would want it to be in an anticoagulated stage. Sodium oxalate and heparin are both anticoagulants and therefore would prevent the clotting of blood. A chilled test tube would not have any effect directly, except the fact that low temperatures delays clotting. The test tube containing calcium bicarbonate would be unsuitable, as calcium is one of the factors required for clotting and hence would accelerate the clotting procedure.. Thus, the correct answer is A. 

A test tube containing calcium bocarbonate should not be used for storing blood for analysis as the blood would clot immediately due to the presence of calcium.