GENERAL HISTOLOGY

Detailed explanation-1: -Finally, the pH in the small intestine is changed through the use of bile-an alkaline substance produced by the liver. Succus entericus or intestinal juice produced by the intestine is also alkaline in nature to allow functioning of enzymes like trypsin, lipase etc.

Detailed explanation-2: -The intraluminal pH is rapidly changed from highly acid in the stomach to about pH 6 in the duodenum. The pH gradually increases in the small intestine from pH 6 to about pH 7.4 in the terminal ileum.

Detailed explanation-3: -The pH of small intestine is about 7-8 which is slightly alkaline in nature. The pancreas secretes bicarbonate ions in small intestine which also neutralises acidic pH of food from stomach and creates an alkaline pH required in small intestine.

Detailed explanation-4: -Pancreatic juice makes the medium in the small intestine alkaline. It neutralizes the acidity of the chyme that comes from the stomach. Alkaline medium is required for the digestion of fats and the action of pancreatic enzymes.

Detailed explanation-5: -After swallowing, the food reaches the stomach where upper and lower parts of stomach have different pH values. The upper part has a pH of 4−6.5, while the lower part is highly acidic with a pH of 1.5−4.0. It then enters the intestine which is slightly alkaline, with a pH of 7−8.5.