biology vs life science

biology and life science both are nouns.

Word	Noun	Adjective	Verb	Adverb
biology	Yes	No	No	No
life science	Yes	No	No	No

As nouns, life science is a hypernym of biology; that is, life science is a word with a broader meaning than biology:

biology: the science that studies living organisms
life science: any of the branches of natural science dealing with the structure and behavior of living organisms

Other hypernyms of biology include bioscience.

biology (noun)	life science (noun)
the science that studies living organisms	any of the branches of natural science dealing with the structure and behavior of living organisms
all the plant and animal life of a particular region
characteristic life processes and phenomena of living organisms