What Causes the Opening and Closing of the Heart Valves

question 110

Multiple Choice

What causes the opening and closing of the heart valves?

• A) stimulation by the sympathetic and parasympathetic nerves
• B) a pressure difference on the two sides of the valve
• C) Na⁺ and K⁺ fluxes during ventricular depolarization
• D) turbulent flow in the atria and ventricles
• E) the action of the papillary muscles and chordae tendineae

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Definitions:

Carbon-14

A carbon isotope that emits radiation, utilized in radiocarbon dating to ascertain the age of organic matter.

Trenches

Deep, narrow depressions in the ocean floor, typically resulting from the subduction of one tectonic plate under another.

Sediment

Particles of organic or inorganic matter that accumulate in a solid layer on the floor of water or on any surface.

Strike-Slip Fault

A type of fault where rock masses slide horizontally past each other.