The Determinant of Whether Heart Valves Are Open or Closed

question 63

True/False

The determinant of whether heart valves are open or closed is the pressure difference across them.

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Definitions:

Oceanic Province

A large, biogeographic region of the ocean characterized by distinct environmental conditions and marine life.

Pelagic Zone

The open ocean zone, far from shore and above the ocean floor, inhabited by a variety of marine species.

Brittle Stars

Echinoderms characterized by their long, slender arms, which are distinct from the central disk.

Tube Worms

Marine invertebrates belonging to several different families, known for living in protective tubes they construct, which can be found in various ocean environments including hydrothermal vents.