The Following Phylum Is Characterized by Having a Hydrostatic Skeleton

question 58

Multiple Choice

The following phylum is characterized by having a hydrostatic skeleton:

• A) Mollusca.
• B) Annelida.
• C) Cnidaria.
• D) Porifera.
• E) Platyhelminthes.

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Definitions:

Irregular Bones

Bones that do not fall into the standard shape categories (long, short, flat), having complex shapes that provide protection, support, and leverage, such as the vertebrae.

Yellow Marrow

Connective tissue filling the cavities of bones; consists primarily of reticular fibers and fat cells; replaces red marrow in long bones and the skull.

Adipose Tissue

A type of body tissue containing stored fat that serves as a source of energy, provides insulation and protection to organs.

Vitamin D

A fat-soluble vitamin that is essential for maintaining healthy bones and teeth by facilitating calcium and phosphorus absorption.