bongu -bog-bo'u- gismu

x1 is a/the bone/ivory [body-part], performing function x2 in body of x3; [metaphor: calcium].

x2 is likely an abstract: may be structure/support for some body part, but others as well such as the eardrum bones; the former can be expressed as (tu'a le ); cartilage/gristle (= ranbo'u), skeleton (= bogygreku). See also greku, denci, jirna, sarji.

In notes:

denci
x1 is a/the tooth [body-part] of x2; (adjective:) x1 is dental.
greku
x1 is a frame/structure/skeleton/outline supporting/load-bearing/determining the form of x2.
jirna
x1 is a/the horn [body-part] of x2; [metaphor: pointed extremity].
sarji
x1 supports/holds up/is underpinning of/[helps] x2 against force/opposition x3 with/by means x4.
bogjinme
x1 is calcium.
bogypu'o
p1 is a quantity of bone meal, made from bone p2=b1.
kamjybo'u
k1=b1 is a vertebra of b3 ; b3 is a vertebrate.
mebybo'u
b1=m1 is a/the frontal bone [os frontale] performing function b2 in body of b3=m2
ranbo'u
b1=r=1 is a/the cartilage/gristle [body-part], performing function b2 in body of b3.
selbo'u
x2=b1 is bone, performing (abstract) function x1=b2 in organism x3=b3.
srubo'u
s1=b1 is a rib of s2=b2.
terbo'u
x3=b1 is bone, performing (abstract) function x2=b2 in organism x1=b3.
kartilago
x1 is/contains cartilage, performing function x2 in body of x3.
ongu
x1 is a bone in or originating from the body of x2.
verteba
x1 is a vertebra of body or body-part x2