Re: agar

BHI Agar is Brain Heart Infusion Agar. This means that the nutrients in the agar 
are from the brain and heart of the cow. These organs are dried and ground into 
a fine dust and digested with enzymes that is then used to make the media called 
BHI Agar. We humans eat beef becasue it provides a lot of nutrients that are 
helpful for us to grow. The same is true of the media produced from the brain 
and heart of the cow. It provides a lot of nutrients that are able to help the 
bacteria to grow. This medium is what we call a rich media. The nutrient content 
is very complex have all of the things most organisms might need to live.

Other media that do not have as rich have a more limited variety and 
concentration of various nutrients and thus prohibit growth of certain 
organisms.