Option H Further human physiology 2. Digestion. Ms.TRS. H2.1 Gland Secretions into the alimentary canal. Features of exocrine cell. Rough Endoplasmic reticulum is usually at the base of the cell and is the site of enzyme synthesis.
Rough Endoplasmic reticulum is usually at the base of the cell and is the site of enzyme synthesis.
(b) Golgi Apparatus for post translation modification of the enzymes.
(c) Granular substances often called zymogens contain the inactive precursors of the digestive enzymes. The enzymes are proteases and the inactive form prevents auto digestion of cellular proteins.
Other features: there are tight junctions between the adjacent cells and there is a small microvilli border.
Exocrine glands release their secretions into a duct. There are three different methods of secretion:1H2.2 The structure of the exocrine gland
Enzyme immobilisation is when the protein molecule is attached to a fixed surface.
Being fixed to the membrane of the epithelium of the duodenum is more efficient since the enzyme is not removed (reused) and can be linked to secondary functions including membrane transport.
Products are released close to the membrane for rapid transport to the membrane
Digestion of the disaccarides(maltose)can occur early in the digestive system
Even when the epithelial cell is rubbed off, the enzyme action can still continue.
Pepsinogen is the inactive precursor of Pepsin.Pepsinogen in secreted by the Chief cells in the gastric pits of the stomach.HCl acid is secreted from the parietal cells and activates the pepsinogen to pepsin in the lumen of the stomach.