Limestone Consists of Rock Made from ____

question 9

Multiple Choice

Limestone consists of rock made from ____.

• A)carbon dioxide
• B)carbonic acid
• C)sodium bicarbonate
• D)calcium carbonate
• E)carbon silicate

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Definitions:

Purkinje Fibers

Specialized fibers located in the heart that conduct electrical impulses responsible for the rhythm of the heart muscle.

Cardiac Conduction

The system of electrical signals that initiate and coordinate the contractions of the heart muscle, ensuring it beats in an efficient and synchronized manner.

AV Node

The Atrioventricular Node, a part of the heart's electrical system that delays the transmission of electrical impulses from the atria to the ventricles.

Semilunar Valves

Heart valves located at the exits of the right and left ventricles of the heart, preventing backflow of blood into the ventricles; includes the aortic and pulmonary valves.