________ Is a Pure Substance Composed of Atoms of Only

question 137

Multiple Choice

________ is a pure substance composed of atoms of only one kind.

• A) element
• B) macromolecule
• C) ion
• D) isotope
• E) compound

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Definitions:

Receptor Sites

Specific regions on the surface of a cell or within a cell where molecules such as hormones, drugs, or neurotransmitters, can bind to elicit a physiological response.

Endocrine Glands

Glands of the endocrine system that release hormones directly into the bloodstream to regulate various body functions.

Hormones

Chemical messengers that are secreted by glands in the endocrine system and travel through the bloodstream to target organs.

Dangerous Situation

A scenario in which there is a high risk of harm or injury to individuals or property.