A bacterial cell will make an endospore when it is low on food so it can survive until there is more food available in the environment. An endospore will actually contain all of the important parts of the bacterial cell, such as its DNA. Only two genera of bacteria can undergo sporulation to form endospores. They are the "Bacillus" and "Clostridium" species. Bacteria that can form endospores but are not in the endospore state are known to be in their vegetative state.