The Most Unique Feature of the Echinoderms Is Their

question 61

Multiple Choice

The most unique feature of the echinoderms is their:

• A) digestive system.
• B) nervous system.
• C) closed circulatory system.
• D) water vascular system.
• E) mantle.

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Definitions:

Epicardium

The outermost layer of the heart wall, composed of connective tissue and fat, providing lubrication for the heart.

Oxygen-rich Blood

Blood that has been oxygenated in the lungs and is carried to the body's tissues.

Pulmonary Circuit

The pathway by which blood travels from the heart to the lungs to be oxygenated and then back to the heart.

Systemic Circuit

The part of the cardiovascular system that carries oxygenated blood away from the heart to the body and returns deoxygenated blood back to the heart.