Lymph tissue in the head and neck.

Lymph nodes play an important part in the body's defense against infection. Swelling might occur even if the infection is mild or not apparent.

Review Date: 12/22/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org).

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