There are five digestive juices; saliva, gastric juice, pancreatic juice, succus entericus (intestinal juice) and bile. The necessity for so many digestive juices is that -(a) One juice does not contain all the enzymes necessary for digesting all the different types of foodstuffs. For instance, saliva contains only carbohydrate-splitting enzymes; whereas gastric juice contains both fat- and protein -splitting enzymes [...]
In this article we will discuss about:- 1. Nerve Supply of Salivary Glands 2. Mechanical Effects of Salivary Secretion 3. Observations 4. Rate of Flow and Composition 5. Adaptability 6. Disturbances. Nerve Supply of Salivary Glands: The salivary centre consists of superior and inferior salivary nuclei in the reticular formation of the medulla. The salivary glands receive double nerve supply—both [...]
On closer study it is found that pancreatic secretion consists of two phases: 1. Nervous Phase 2. Chemical Phase. 1. Nervous Phase: Pancreatic secretion starts 1—2 minutes after taking food. When the vagi are cut, the secretion is abolished. This proves that the initial phase of pancreatic secretion is a reflex response. The stimulus for this reflex arises in the [...]