The First Heart Sound (Lub) Is Produced by the Closing

question 28

Multiple Choice

The first heart sound (lub) is produced by the closing of the ____ and ____ valves.

• A) aortic semilunar; pulmonary semilunar
• B) right atrioventricular; aortic semilunar
• C) left atrioventricular; pulmonary semilunar
• D) right atrioventricular; left atrioventricular
• E) mitral; left atrioventricular

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Definitions:

Lead Arrangement

In electrocardiography, refers to the placement and organization of electrode leads on the body to measure cardiac activity.

Electrodes

Conductive materials used to establish electrical contact with a nonmetallic part of a circuit, often seen in medical devices or for delivering electrical therapy.

ECG

Also known as an electrocardiogram, it's a medical test that measures the electrical activity of the heart to identify various heart conditions.

Precordial

Pertaining to that area of the chest wall over the heart for the placement of ECG chest leads.