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URL of this page: //medlineplus.gov/ency/article/002353.htm

Enzyme

Enzymes are complex proteins that cause a specific chemical change. For example, they can help break down the foods we eat so the body can use them. Blood clotting is another example of enzymes at work.

Enzymes are needed for all body functions. They are found in every organ and cell in the body, including in the:

  • Blood
  • Intestinal fluids
  • Mouth (saliva)
  • Stomach (gastric juice)

References

Hall JE, Hall ME. Genetic control of protein synthesis, cell function, and cell reproduction. In: Hall JE, Hall ME, eds. Guyton and Hall Textbook of Medical Physiology. 14th ed. Philadelphia, PA: Elsevier; 2021:chap 3.

Taber's Medical Dictionary Online website. www.tabers.com/tabersonline. Accessed March 16, 2023.

Review Date 2/2/2023

Updated by: Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.