Can you Write a paragraph describing the instances of mechanical and chemical digestion that occur during the digestive process?

Answer 1

The Oral Cavity has limited digestion of carbohydrates and lipids. It also has teeth that chew food into smaller pieces to give larger surface area for enzymes to work.

The Tongue shows secretion of mucins and the enzyme lingual lipase.

The parotid salivary glands produce a serous secretion containing large amounts of salivary amylase, an enzyme that breaks down starches (complex carbohydrates).

Cells of the submandibular glands secrete a mixture of buffers, glycoproteins called mucins, and salivary amylase.

The primary function of the esophagus is to convey solid food and liquids to the stomach.

The stomach disrupts chemical bonds in food material through the action of acids and enzymes,

production of intrinsic factor, a glycoprotein whose presence in the digestive tract is required for the absorption of vitamin B12in the small intestine.

Parietal cells in the stomach secrete hydrochloric acid (HCl).

Chief cells secrete pepsinogen, an inactive proenzyme. Pepsinogen is converted by the acid in the

gastric lumen to pepsin, an active proteolytic enzyme.

Glands in the pylorus produce primarily a mucous secretion, rather than enzymes or acid. In addition, several types of enteroendocrine cells are scattered among the mucus-secreting cells.

Gastrin is produced by G cells, which are most abundant in the gastric pits of the pyloric antrum.

The pyloric glands also contain D cells, which release somatostatin, a hormone that inhibits the release of gastrin.

The stomach is a holding tank in which food is saturated with gastric juices and exposed to stomach acids and the digestive effects of pepsin.

The mucosa of the small intestine produces only a few of the enzymes involved.

The pancreas provides digestive enzymes, as well as buffers that help neutralize chyme.

Brush border enzymes are integral membrane proteins located on the surfaces of intestinal microvilli.

These enzymes perform the important digestive function of breaking down materials that come in contact with the brush border.

Enterokinase is one brush border enzyme that enters the lumen in this way, does not directly participate in digestion, but it activates a key pancreatic proenzyme, trypsinogen.

Intestinal glands also contain enteroendocrine cells responsible for the production of several intestinal hormones, including gastrin, cholecystokinin, and secretin.

The pancreas is primarily an exocrine organ, producing digestive enzymes and buffers.

The specific pancreatic enzymes involved include the following:

Pancreatic alpha-amylase, a carbohydrase- an enzyme that breaks down certain starches.

Pancreatic alpha-amylase is almost identical to salivary amylase.

Pancreatic lipase, which breaks down certain complex lipids, releasing products (such as fatty acids) that can be easily absorbed and nucleases, which break down nucleic acids.

Proteolytic enzymes, which break certain proteins apart. The proteolytic enzymes of the pancreas

include proteases, which break apart large protein complexes, and peptidases, which break small peptide chains into individual amino acids