lens nucleus vs body structure

lens nucleus and body structure both are nouns.

Word	Noun	Adjective	Verb	Adverb
lens nucleus	Yes	No	No	No
body structure	Yes	No	No	No

As nouns, body structure is a hypernym of lens nucleus; that is, body structure is a word with a broader meaning than lens nucleus:

lens nucleus: the central structure of the lens that is surrounded by the cortex
body structure: a particular complex anatomical part of a living thing and its construction and arrangement

Other hypernyms of lens nucleus include anatomical structure, bodily structure, complex body part, structure.

lens nucleus (noun)	body structure (noun)
the central structure of the lens that is surrounded by the cortex	a particular complex anatomical part of a living thing and its construction and arrangement