The only difference between broth and agar media is that broths do not contain an agar component. We use broth tubes primarily for specific assays, or (rarely) for bacteria that will not form colonies on a solid surface. Unlike preparation of agar plates, tubes are prepared with media already in the incubation vessel.
Similarly one may ask, what is Agar made out of?
The gelling agent in agar is an unbranched polysaccharide obtained from the cell walls of some species of red algae, primarily from the genera Gelidium and Gracilaria. For commercial purposes, it is derived primarily from Gelidium amansii. In chemical terms, agar is a polymer made up of subunits of the sugar galactose.
What is the purpose of the agar in the media?
Nutrient Agar is a general purpose, nutrient medium used for the cultivation of microbes supporting growth of a wide range of non-fastidious organisms. Nutrient agar is popular because it can grow a variety of types of bacteria and fungi, and contains many nutrients needed for the bacterial growth.
What are peptones and agar?
Peptone is a mixture of proteins and amino acids that is obtained by breaking down natural products such as animal tissues, milk and plants. The function of peptone in nutrient agar is to provide a protein source so that micro-organisms can grow.