biological science vs pubescent

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

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

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

biological science (adjective)	pubescent (adjective)
	covered with fine soft hairs or down
	(of animals especially human beings) having arrived at the onset of puberty (the age at which sex glands become functional) but not yet fully mature