Question

which of these is not a function of the stomach?
begins the digestion of protein
produces a hormone to increase its own secretions
begins the digestion of starch
permits digestion to take place gradually
question 3
1 pts
saliva contains
bicarbonate
water
amylase
all of the choices
mucins
question 4
1 pts
secretion of pancreatic enzymes is stimulated by the hormone secretin and secretion of bicarbonates is stimulated by the hormone cholecystokinin
true
false

Explanation:

• First question: The stomach begins protein digestion (pepsinogen is converted to pepsin in the acidic environment of the stomach). Gastrin (produced by G - cells in the stomach) increases gastric secretions. The stomach stores food and allows for gradual digestion. However, starch digestion begins in the mouth with salivary amylase.
• Second question: Saliva contains water (main component), bicarbonate (buffers the oral pH), amylase (starts starch digestion), and mucins (for lubrication). So, saliva contains all of these components.
• Third question: Secretin stimulates the secretion of bicarbonates from the pancreas (to neutralize chyme in the duodenum), and cholecystokinin (CCK) stimulates the secretion of pancreatic enzymes.

Answer:

• First question: begins the digestion of starch
• Second question: all of the choices
• Third question: False