Human Digestion The digestive process begins as soon as food enters the mouth. Saliva begins to immediately break down sugars and starches, while the teeth grind down the food. Food then enters the esophagus and is swallowed, where it then enters the stomach for further breakdown by way of stomach acids. Very little of the food is actually digested in the stomach. Instead, the acids work to break down the food for easier digestion in the intestines.
CheckPoint: Human Digestion I am describing, the path food follows through the digestive system and how digestion occurs in each of the following parts of the digestive system. I am including in the description of other organs or components of the digestive system, including: * Large intestine * Mouth * Small intestine * Stomach After the food enters the mouth and after being moistens and chewed by the teeth, the food then converts into a Bolus. Bolus as mentioned refers to the softened mass of munched on food that passes through the digestive system. The bolus then exits the mouth and progresses into the pharynx. The bolus then moves down into the esophagus, which follows to the stomach.
The small intestine is the principal site of digestion and absorption. Enzymes from the pancreas, liver, gallbladder, and the small intestine itself combine to break down nutrients so that they can be absorbed. The pancreas supplies enzymes to digest proteins, fats and carbohydrates. The live produces bile required for emulsification of fat, and the gallbladder stores the bile until it is needed. The absorption of nutrients in the small intestine is facilitated by tiny projections called villi, which provide more surface area for absorption.
Digestion first begins in the mouth. The saliva in our mouths is what begins the process of digestion. As the food is chewed, a clear liquid called saliva is produced to help break down and moisten the food so that it is easy to swallow. The saliva is produced in a salivary gland located under the tongue. It coats the chewed food and transforms it into what is called a bolus.
2.2 What happens in the cephalic stage? Firstly, food is taken into the mouth and then broken down into smaller pieces by ‘mechanical digestion’ (or the using the teeth to break down food). Saliva in the mouth is produced due to the neural reponses which come about from the stimulus of the eyes, head, smell etc. An enzyme in the saliva called amylase begins the chemical digestion by breaking down ‘complex carbohydrates into simple sugars’. When the food is ready to be swallowed, the food is now called a soft mass called a ‘bolus’.
The Ventromedial Nucleus is the Satiety Centre. Satiety is the unconscious physiological process that stops you eating. The VMN provides the signal to stop eating when it picks up hormonal messages. For example, when food is being digested the level of the hormone CCK in the bloodstream is high. This stimulates receptors in the VMN.
After this the food is taken down a long tube, called the oesophagus, which takes the food from the mouth to the stomach. The movement of the food is helped by waves of contraction of the muscle surrounding the oesophagus, this is called peristalsis. Once the food enters the stomach a ring of muscle at the exit called the pyloric sphincter contracts and prevents the food from leaving. For the next two to three hours churning movements of the stomach produce further physical breakdown of food. The only chemical digestion that takes place in the stomach is the breakdown of proteins, which is from the meat in the
Once the cobbler enters the mouth, teeth start chopping the food up while the tongue is incorporating it with the saliva from the salivary glands, this converts into a ball of food, called Bolus. The tongue advances the Bolus into the Pharynx, which is responsible for swallowing, through the esophagus. The bolus passes through a sphincter into the stomach. Upon entering the stomach it mixes with an acidy secretion known as Chyme. Some digestion takes place in the stomach few exceptions; the Chyme empties from the stomach into the small intestine within two thru six hours dependent upon the size of the meal (Grosvenor & Smolin, 2006).
Digestion of carbohydrates begins in the mouth as mentioned earlier with the enzyme amylase which is present in the saliva. This breaks the carbohydrates into their simpler subunits (saccharide forms). In the stomach, the carbohydrates are converted into chyme with the peristaltic action of the stomach. Next, the chyme will pass into the duodenum. At the introduction to the duodenum, alpha amylase is secreted by the pancreas and further breaks down the carbohydrates into primary simple sugars.
So, throughout this paper we will take a look at the procedure, the facility, and the benefits of having weight loss surgery. First, we will look at the procedure of how a weight loss surgery is performed. Gastric Bypass Surgery also commonly called Roux-en-Y is a procedure in which the Doctor goes in and divides the stomach into a larger portion and smaller portion. The smaller portion of stomach is then sewn together or stapled to be capable of only holding a cup of food. This part of the surgery causes people to feel full quickly and eat less.