Pepsinogen I is secreted by chief cells, and pepsinogen II is secreted by pyloric glands. The secretion of pepsinogen is stimulated by vagal stimulation, gastrin, and histamine. Pepsinogen I is mainly found in the body of the stomach, where most acid is secreted. Pepsin is a proteolytic enzyme, whereas pepsinogen is a proenzyme. â¢ Pepsin is the active form of pepsinogen while pepsinogen is the inactive precursor of pepsin. â¢ Unlike the pepsin, pepsinogen is secreted by chief cells and pyloric glands.
A reefer ship is a refrigerated cargo ship; a type of ship typically used to transport perishable commodities which require temperature-controlled transportation, such as fruit, meat, fish, vegetables, dairy products and other foods.
Prior to the development of mechanically cooled reefer units, perishable products were transported in large van trailers containing blocks of ice. A loud engine was mounted on the outside of these 30- to 35-foot (9- to 11-m) trailers, and a fan, driven by the trailerâs motor, was affixed within them, near the front.