Which Element in Smoke Contains Most of the Cancer-Causing Substances

question 11

Multiple Choice

Which element in smoke contains most of the cancer-causing substances?

• A)carbon monoxide
• B)tar
• C)nicotine
• D)carbon dioxide

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Definitions:

Pacemaker

A device implanted in the body that delivers electrical impulses to the heart to regulate the heartbeat.

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.