1. Why is it necessary to maintain aseptic conditions in microbiology? 2. Explain why the following steps are necessary during sub culturing: dFlaming the inoculating loop before and after each inoculation (= b. Cooling the inoculating loop before touching the inoculum/culture ( Flaming the neck of tubes/bottles after capping and before re-capping ( Can pure culture be prepared directly from a mixed culture? Explain your answer. 4. You have been asked to determine the bacterial count in a sample of water. The-number of CFU from 1 ml of a 106 dilution was 43 and 49 on duplicate agar plates.per ml of the original sample of water? (5What is the total number of microorganisms-marks)

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