In today's world, Apex (mollusc) is a topic that has become increasingly relevant and interesting in different areas. Both in the political, social, and economic spheres, as well as in people's daily lives, Apex (mollusc) has captured the attention of millions of individuals around the world. The importance of Apex (mollusc) is reflected in the diversity of opinion and approaches that exist around this topic, as well as in the constant evolution and change it experiences over time. This is why it is crucial to deepen the understanding of Apex (mollusc), analyzing its implications and discussing its different facets. In this article, we will delve into the world of Apex (mollusc), exploring its different dimensions and addressing the debates surrounding this topic that is so relevant today.
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In anatomy, an apex (adjectival form: apical) is part of the shell of a mollusk. The apex is the pointed tip (the oldest part) of the shell of a gastropod, scaphopod, or cephalopod.
The apex is used in end-blown conches.
The word "apex" is most often used to mean the tip of the spire of the shell of a gastropod. The apex is the first-formed, and therefore the oldest, part of the shell. [1] To be more precise, the apex would usually be where the tip of the embryonic shell or protoconch is situated, if that is still present in the adult shell (often it is lost or eroded away).
The phrase apical whorls, or protoconch, means the whorls that constitute the embryonic shell at the apex of the shell, especially when this is clearly distinguishable from the later whorls of the shell, otherwise known as the teleoconch.
Comparison of the apical part and the whole shell of Otukaia kiheiziebisu:
Where this feature is present, the space under the apex of a patellate or patelliform (limpet-like) gastropod shell is called the apical cavity.
The apex of tusk shells is the small, open posterior end, and the opening itself is usually called the apical aperture.
In orthocone cephalopods, the pointed end of the shell is called the apex, and shell growth is away from the apex and toward the aperture. The first chamber of the apex is sometimes called the protoconch.
The apex of a valve of a bivalve shell is the area around what is most commonly the umbo or beak. In some species the embryonic shell or prodissoconch may be present at the apex of each of the two valves.