biological science vs obligate

biological science is a noun but obligate is not a noun.

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

biological science (noun)	obligate (noun)
the science that studies living organisms

biological science (adjective)	obligate (adjective)
	restricted to a particular condition of life

biological science (verb)	obligate (verb)
	bind by an obligation; cause to be indebted
	commit in order to fulfill an obligation
	force somebody to do something