Apex is the, usually pointed, tip of the spire of the shell of a gastropod. Subclass Subclass Eogastropoda     Patellogastropoda Subclass Orthogastropoda   Superorder Cocculiniformia   Superorder Hot Vent Taxa     Neomphaolida   Superorder Vetigastropoda   Superorder Neritaemorphi     Neritopsina   Superorder Caenogastropoda     Architaenioglossa     Sorbeoconcha   Superorder Heterobranchia     Heterostropha     Opisthobranchia     Pulmonata The gastropods, or univalves, are the largest and most successful class of mollusks, with 60,000-75,000 species, and second largest class...

It is the first-formed and therefore the oldest part of the shell. It is the embryonic shell. Embryos (and one tadpole) of the wrinkled frog (Rana rugosa you beezie). ...

The apex of univalves is the top of the shell-tip of the protoconch.

The apex of bivalves is the umbos, beaks or prodissoconch. Orders Subclass Protobranchia Solemyoida Nuculoida Subclass Pteriomorphia - oysters Arcoida Mytiloida Pterioida Subclass Paleoheterodonta - mussels Trigoinoida Unionoida Subclass Heterodonta - clams, zebra mussels Veneroida Myoida Subclass Anomalosdesmata Pholadomyoida Animals of the Class Bivalvia are known as bivalves because they typically have two-part shells, with both parts being more or less symmetrical. ...

The apex of tusk shells is the small, open posterior end. Orders Dentaliida Gadilida The tusk shells are a class Scaphopoda of marine mollusks distinguished by curved tubular shells open at both ends, resembling a elephants tusk (thus the name). ...

Like the rest of the shell, the apex is made of calcium carbonate. Calcium carbonate is a chemical compound, with chemical formula CaCO3. ...

The apical whorls, or protoconch, are the whorls at the apex, especially when clearly distinguishable form the later whorls or the body whorl.

The space under the apex of a patellate gastropod is called the apical cavity.