The Second Heart Sound (S₂)occurs Because of the Closure of The

question 17

Multiple Choice

The second heart sound (S₂) occurs because of the closure of the:

• A) Aortic valve
• B) Tricuspid valve
• C) Aortic and pulmonic valve
• D) A and B

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Definitions:

Carbanion

An organic ion in which a carbon atom has three bonds and bears a negative charge, often an intermediate in organic reactions.

Free Radical

Highly reactive atoms or molecules with unpaired electrons, involved in a variety of chemical processes including polymerization and combustion.

Haloalkane

A class of organic compounds where one or more hydrogen atoms in an alkane (saturated hydrocarbon) are replaced with halogen atoms (such as chlorine, bromine, or iodine).

R or S Description

A system for describing the configuration of chiral centers in molecules, indicating the spatial arrangement of atoms around the center.