The molluscan shell does not contain the:
A) periostracum.
B) prismatic layer.
C) narceous layer.
D) mantle.

Question

Quizplus · Accepted Answer

The mantle is not a part of the molluscan shell. The mantle is the tissue layer that secretes the shell, but once the shell is formed, the mantle is no longer a part of it. The periostracum is the outermost layer of the shell and is composed of organic material. The prismatic layer is the middle layer of the shell and is composed of calcium carbonate crystals arranged in a prism-like structure. The narceous layer is the innermost layer of the shell and is composed of a mixture of calcium carbonate and organic material.

The Molluscan Shell Does Not Contain The