Which of the Following Is a Pure Substance

question 35

Multiple Choice

Which of the following is a pure substance?

• A) blood
• B) block of aluminum
• C) air
• D) orange juice

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Definitions:

Body Surface

The body surface refers to the outermost layer of an organism's body, including the skin in humans, which serves as a protective barrier against the environment.

Tracheal Tubes

A network of air tubes in insects and some terrestrial arthropods that allow for efficient gas exchange directly with body tissues.

Gills

Respiratory organs found in many aquatic organisms, which extract oxygen from water and expel carbon dioxide.

Lungs

Organs of respiration in vertebrates where blood exchanges oxygen and carbon dioxide with the air breathed in.