zoology vs zoological science

zoology and zoological science both are nouns.

Word	Noun	Adjective	Verb	Adverb
zoology	Yes	No	No	No
zoological science	Yes	No	No	No

As nouns, zoology and zoological science are synonyms defined as:

zoology and zoological science: the branch of biology that studies animals

zoology (noun)	zoological science (noun)
the branch of biology that studies animals	the branch of biology that studies animals
all the animal life in a particular region or period