Pancreatic juice is secreted into the pancreatic duct which carries these secretions to the small intestine. The hormone secretin is released by the small intestine when hydrochloric acid enters it from the stomach. The data below show the volume of pancreatic juice released after an injection of secretin. 
State two roles of hydrochloric acid in gastric juice.
a. activation of enzymes/protease/pepsinogen ✓ b. bactericidal action / kills pathogens ✓ c. hydrolysis / breakdown of food ✓
Pancreatic secretions contain sodium hydrogen carbonate, making them basic. Deduce the significance of the response by the pancreas to secretin.
a. secretin stimulates an increase in pancreatic secretions ✓ b. pancreatic secretions are released rapidly / within 10 minutes ✓ c. «NaHCO₃ in pancreatic secretions» neutralises stomach acid / HCl ✓ d. provides optimal conditions for digestion / enzymes «in the small intestine» ✓ e. by 40 minutes no more hydrochloric acid enters the small intestine ✓
State one cause of stomach ulcers.
an infection by Helicobacter pylori / H. pylori OR overuse of NSAIDs /aspirin / ibuprofen ✓
