All of the Following Elements Can Exist as Allotropes Except

question 150

Multiple Choice

All of the following elements can exist as allotropes except ________.

• A)N
• B)Ar
• C)O
• D)S
• E)F

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Definitions:

Epiglottis

A flap of cartilage at the root of the tongue, which is depressed during swallowing to cover the opening of the windpipe.

Uvula

A small fleshy extension at the back of the soft palate which hangs above the throat and plays a role in speech and swallowing.

Upper Esophageal Sphincter

The muscular ring located at the top of the esophagus that controls the passage of food into the esophagus from the throat.

Pharyngeal Phase

A phase in the swallowing process where the bolus is moved from the mouth to the esophagus involving the contraction of pharyngeal muscles.