Final answer:
Agar is used as a solidifying agent in culture media preparation to provide a solid growth surface for bacteria. The steps involved in culture media preparation depend on the type of media being prepared.
Step-by-step explanation:
Agar is used in culture media preparation as a solidifying agent. It provides a solid growth surface for bacteria to reproduce and form colonies. Agar, which is derived from red seaweed, is preferred because it is inert and non-nutritive. Derived from red seaweed, agar is a polysaccharide compound that is inert and non-nutritive, making it an ideal solidifying agent. When dissolved in hot water and cooled, it forms a gel-like substance that allows for the growth and observation of bacterial colonies. The steps involved in culture media preparation depend on the type of media being prepared. For liquid media (broth), the ingredients are mixed together and sterilized. For solid and semi-solid media, agar is added to the mixture and then sterilized. The media is then poured into plates or tubes and allowed to solidify before use.