Question

Describe the steps of focusing to view a specimen.

Describe how to use oil immersion. Why is oil immersion used in microbiology?

Describe the technique of streaking for isolation. Why is it used in microbiology?

please no handwritten or cursive written responses. No uploaded pictures please only text.

Answer 1

First place the specimen on the stage, in between clips. Then puton the light source. Select proper objective lenses like 10x or 40x etc. Then adjust the course and fine adjustment knobs by seeing through eye piece.

Oil immersion greatly increase the Resolving power and Refractive index, which finally leads to clarity image. After prepared the Specimen, then add 1 or 2 drops of Cidar wood oil, then coverit with glass cover slip.

Streaking method is used for Isolation of pure culture from mixed culture. This is a type of dilution where progressive getting of heterogeneous population into homogenous population. It is practice on agar plates