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

1. Chilled test tube

2. Test tube containing heparin

3. Test tube containing sodium oxalate

4. Test tube containing calcium bicarbonate

Subtopic:  Obtaining Copy of Gene from Donor DNA |
AIPMT - 2004
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