This depends on the Definition of "Shell Structure" Most laypersons class a car as a shell structure. But for engineering purpose's?
Enzymes have this structure. The way that they are folded determines their function.
A vestigial structure is one that no longer appears to service a purpose in maintaining homeostasis. An example is the vermiform appendix.
One of the primary functions of external walls is to provide an efficient weathershield. They prevent the penetration of moisture, which can have a detrimental effect on the internal structure.
exaptation
Organized.
Organized.
Organized.
A memo really doesn't have much of a structure and the purpose is to inform or remind yourself or others of something.
mounika
structure is a collection of variables of different datatypes.
A structure is identified as an object built for a specific purpose (i.e. dams, bridges, etc...). A bulding is also a structure but with a specific purpose of housing occupants (home, hotel, work offices, etc).
A vestigial structure is a structure that an organism still has but no longer serves any real definite purpose. In this case, the whiskers on a cat serve a vital purpose, so they are not vestigial structures.
Cell wall
the pistil is the female reproductive structure
to provide structure to plant cells, like how bones provide our bodies with structure
In what ways do audience, purpose, tone, and structure affect the formatting of the memo and acedemic paper