Saliva

Definition

Saliva is a clear, watery fluid produced by salivary glands in the mouth. It contains enzymes, antibodies, and other substances that aid in digestion and provide immune defense.

5 Must Know Facts For Your Next Test

1. Saliva contains the enzyme amylase, which begins the breakdown of carbohydrates in the mouth.
2. Lysozyme in saliva acts as an antimicrobial agent by breaking down bacterial cell walls.
3. Saliva has immunoglobulin A (IgA), an antibody that plays a crucial role in mucosal immunity.
4. The normal microbiota of the mouth includes various bacteria that are kept in balance by components of saliva.
5. Adequate saliva production is essential for oral health, as it helps prevent infections like dental caries and gingivitis.

Review Questions

• What enzyme present in saliva initiates carbohydrate digestion?
• How does lysozyme in saliva contribute to innate host defenses?
• What role does immunoglobulin A (IgA) play in the immune functions of saliva?

Related terms

Amylase:

An enzyme found in saliva that breaks down starch into sugars.

Lysozyme:

An enzyme present in various body fluids including saliva, responsible for breaking down bacterial cell walls.

Immunoglobulin A (IgA): An antibody found in mucous secretions, including saliva, that plays a key role in mucosal immunity.