The subject-matter of biology is mediated by objects. From a specified
and general term of object the term ''biological object'' can be deri
ved as a special term of object. Living objects have some special qual
ities in comparison with nonliving objects, which must be taken into c
onsideration by the production of biological knowledges. Standardized
objects and theoretical essential objects have a special importance fo
r theoretical generalizations. Criterions for the suitability of objec
ts are suitable both for research and teaching. The discussion of poss
ible contents of a biological theory of object is biotheoretically sig
nificant.