taxonomy vs biological science

taxonomy and biological science both are nouns.

Word	Noun	Adjective	Verb	Adverb
taxonomy	Yes	No	No	No
biological science	Yes	No	No	No

taxonomy (noun)	biological science (noun)
practice of classifying plants and animals according to their presumed natural relationships	the science that studies living organisms
(biology) study of the general principles of scientific classification
a classification of organisms into groups based on similarities of structure or origin etc