What Is the Origin of the Shell of the Molluscan

question 36

Multiple Choice

What is the origin of the shell of the molluscan clam?

• A) Clam shell is a form of skeletal bone tissue
• B) Calcium carbonate is crystallized out of the salts in the surrounding water by astrocytes on the surface of the epidermis
• C) Heavy layers of chitin are secreted by the molluscan epidermis
• D) Mucous glands in the molluscan epidermis secrete the calcium carbonate of the shell
• E) Mucous glands in the molluscan epidermis secrete a chitin that is then stiffened by calcification

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Definitions:

Stock Purchases Register

A ledger or record keeping log for tracking all purchases of stock inventory over a period.

Voucher System

An accounting system used to authorize and record transactions such as purchases or sales.

Purchases Journal

A record of all purchases of goods and services on credit, aimed at simplifying the accounting process.

Voucher Register

A record of vouchers that have been prepared, detailing amounts to be paid, accounts affected, and supporting documentation.