NSG 5003 Chapter 40 Structure and Function of the Digestive System Exam with Q and A

NSG 5003 Chapter 40 Structure and Function of the Digestive System Exam with Q and A In the mouth and stomach, salivary -amylase initiates the digestion of which nutrients? a. Proteins b. Carbohydrates c. Fats d. Fiber ANSWER ANS: B Salivary -amylase is an enzyme that initiates only carbohydrate digestion in the mouth and stomach. Which elements in saliva protect against tooth decay? a. Salivary -amylase and ptyalin b. Secretin and IgA c. Endogenous enamelin and salivary -amylase d. Exogenous fluoride and a pH of 7.4 ANSWER ANS: D The bicarbonate concentration of saliva sustains a pH of approximately 7.4, which neutralizes bacterial acids and prevents tooth decay. Exogenous fluoride (e.g., fluoride in drinking water) is absorbed and then secreted in the saliva, providing additional protection against tooth decay. Saliva contains which immunoglobulin (Ig)?