Question

Why is it important to quickly cool tubes filled with agar in an ice bath, when the inoculation of the brain heart infusion agar deeps?

Answer 1

Because to make oxygen gradient throughout the tube it is important to quickly cool tubes after mixing bacterial inoculum

Once the agar solidifies,an oxygen gradient is created with atmospheric oxygen concentration at the top of tube and little or no oxygen at bottom of the tube

The bacteria only grow in the part of tube where their oxygen requirements are fulfil and localised in that area

And by that we can find the oxygen requirements of that organism(which was our aim).