You Recover a Fossil from the Devonian Period That Appears

question 93

Short Answer

You recover a fossil from the Devonian period that appears to be a large sporophyte with a stem that grows in segments above whorls of true leaves.Based on this description, you identify the specimen as a _______, which is one member of a clade containing only itself and ferns.

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Definitions:

Epicardium

Serous membrane covering the surface of the heart; also called visceral pericardium.

Pericardial Fluid

Viscous fluid contained within the pericardial cavity between the visceral and parietal pericardium; functions as a lubricant.

Heart Valves

Structures within the heart that maintain unidirectional flow of blood by opening and closing depending on the pressure differential.

Systemic Circulation

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