National Certified Addiction Counselor, Level I (NCAC I) Practice Exam

Endorphins and enkephalins are classified as what type of molecules?

1. Hormones

2. Natural peptides

3. Enzymes

4. Neurotransmitters

The correct answer is: Natural peptides

Endorphins and enkephalins are classified as natural peptides because they are made up of chains of amino acids. Specifically, they are neuropeptides produced in the brain and act as neurotransmitters that modulate pain and promote feelings of pleasure and well-being. Their classification as natural peptides highlights their structural characteristics, as these molecules are synthesized by the body from precursor proteins through enzymatic actions. While they do indeed have neurotransmitter functions, their primary classification underlines their peptide nature rather than their role in neurotransmission or hormone functions, which could lead to confusion. This distinction is crucial in understanding their biochemical properties and physiological roles in the body.