Which Three Elements Constitute More Than 90 Percent of a Cell

question 59

Multiple Choice

Which three elements constitute more than 90 percent of a cell?

• A)oxygen, potassium, sodium
• B)oxygen, hydrogen, sodium
• C)oxygen, hydrogen, carbon
• D)carbon, hydrogen, sodium

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Definitions:

Sigmoidoscopy

A medical examination of the sigmoid colon by means of a flexible tube inserted through the anus to check for cancer, polyps, and other anomalies.

Gastroscopy

A diagnostic procedure that involves using a gastroscope to visually examine the interior of the stomach.

Colonoscopy

A medical procedure using a camera to examine the interior lining of the colon and rectum.

Proctoscopy

A medical procedure where a special instrument, called a proctoscope, is used to examine the anal cavity, rectum, or sigmoid colon.