Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Travel Brochure John Zhou Digestion Oral Cavity Abdominal Cavity Pelvic Cavity EXIT Oral Cavity • What’s oral cavity? • It’s the opening or the hollow part of the mouth. • It contains the mouth, tongue, teeth, salivary glands, pharynx… mouth lips teeth salivary glands pharynx epiglottis esophagus peristalsis Oral Cavity Mouth • In the mouth, it has two categories of digestion, which are the chemical and physical digestion. • For lips and teeth, they are physical digestions. • The salivary glands are chemical digestions. Lips • Lips are a visible body part at the mouth of humans and many animals. Lips are soft, movable, and serve as the opening for food intake . • Lips also help to lead the food to the teeth. Teeth • Tooth is usually started by the action on the outside of the teeth of acid produced by bacteria feeding mostly on sugary foods and sweets we eat. This has several stages. It consists of a sticky film of bacteria and other micro-organisms, together with materials from the saliva and foods we eat. This is relatively easy to remove by brushing, and can be felt by the brushing, and can be felt by the tongue. If this is allowed to build up over a period of remove, and it provides sites for bacterial growth. Salivary Glands • There are three main glands, which are parotid glands, submandibular glands and sublingual glands. They produce the enzyme called amylase to help to digest. • Their main function is produce the saliva for the mouth, which refer to the chemical digestion. Saliva is the liquid that has a little bit acid and can help to digest the food with the teeth (physical digestion). Sublimandibular Glands • Approximately 70% of saliva in the oral cavity is produced by the submandibular glands, even though they are much smaller than the parotid glands. You can usually feel this gland, as it is in the upper neck and feels like a rounded ball. Parotid Glands • It is one of a pair being the largest of the salivary glands, it secretes saliva through Stensen's ducts into the oral cavity, to facilitate mastication and swallowing and to begin the digestion of starches. The secretion produced is mainly serous in nature Sublingual Glands • The sublingual glands are a pair of glands located beneath the tongue, anterior to the submandibular glands. The secretion produced is mainly mucus in nature, however it is categorized as a mixed gland. Unlike the other two major glands, the ductal system of the sublingual glands do not have striated ducts, and exit from 8-20 excretory ducts. Approximately 5% of saliva entering the oral cavity come from these glands. Pharynx Pharynx • As you can see in last page, the picture show the structure of the pharynx. It’s very important in the whole digestion process. • It kind of gate for entering the stomach, in order to digest the food, which can’t be digested in the mouth. • Most of digestions happen in the stomach or near the stomach are chemical digestion. Epiglottis • The epiglottis guards the entrance of the glottis, the opening between the vocal folds. It is normally pointed upward while one is breathing with its underside functioning as part of the pharynx, but while one is swallowing, elevation of the hyoid bone draws the larynx upward; as a result, the epiglottis folds down to a more horizontal position, with its superior side functioning as part of the pharynx. Esophagus BACK TO HOME • The esophagus is an organ in vertebrates which consists of a muscular tube through which food passes from the pharynx to the stomach. During swallowing, food passes from the mouth through the pharynx into the esophagus and travels to the stomach due to the process, which called peristalsis. ** peristalsis: Smooth muscle lining the esophageal wall pushes food down. Abdominal Cavity Stomach Duodenum Pancreas Gall Bladder Liver Stomach • Stomach is located between esophagus, duodenum and small intestine. It is the second step of digestion, which is following the swallowing. • The stomach is a muscular, hollow, dilated part of the digestion system, which plays a very important role. It secretes protein-digesting enzymes called pepsin. It’s produced by the hydrochloric acid and pepsinogen. In order to digest the protein. Stomach • Stomach also has two sphincters: cardiac sphincter and pyloric sphincter. • Cardiac sphincter- it control the upwards part of the stomach, in order to avoid the acid chyme climbs up to the esophagus. • Pyloric sphincter-let small amounts of acid chyme to enter the intestine to help digest the food. Duodenum • The duodenum is the first section of the small intestine in most higher vertebrates. • The duodenum is largely responsible for the breakdown of food in the small intestine, using enzymes. • The duodenum also regulates the rate of emptying of the stomach hormonal pathways. Duodenum Liver • This organ plays a major role in metabolism and has a number of functions in the body, including glycogen storag e, decomposition of red blood cells, plasma protein synthesis, hormon e production, and detoxification. It lies below the diaphragm in the abdominal-pelvic region of the abdomen. It produces bile, an alkaline compound which aids in digestion the emulsification of lipids. CHALLENGE • Try to recite last page words about the liver, then name the number of this diagram below. Gall Bladder • The gallbladder is a hollow system that sits just beneath the liver. In adults, the gallbladder measures approximately 8 centimeters (3.1 in) in length and 4 centimeters (1.6 in) in diameter when fully distended. It is divided into three sections: funds, body, and neck. The neck tapers and connects to the billiard tree the cystic duct, which then joins the common hepatic duct to become the common bile duct. At the neck of the gallbladder is a mucosal fold called Hartmann's pouch, where gallstones commonly get stuck. The angle of the gallbladder is located between the costal margin and the lateral margin of the rectus abdominals muscle. Pancreas • The pancreas as an exocrine gland helps out the digestive system. It secretes pancreatic fluid that contains digestive enzymes that pass to the small intestine. These enzymes help to further break down the carbohydrates, proteins, and lipids (fats) in the chyme, like pancreatic amylases, trypsin, lipase, and sodium biocarbonate. POP QUIZ Lower Abdominal Cavity • Small intense • Large intense • appendix Small Intense • The small intestine is the part of the gastrointestinal tract following the stomach and followed by the large intestine, and is where much of the digestion and absorption of food takes place. • The primary function of the small intestine is the absorption of nutrients and minerals found in food. Small Intestine • Villi--the singular of which is villus, are finger-like projections in the small intestine that help absorb food more efficiently in the body. The small intestine is an organ in the body in which most digestion occurs. Food entering into the body is liquefied and partially digested in the stomach. It then passes into the small intestine. The villi are the parts that absorb nutrients from food and pass them into the bloodstream. • Villi are also covered with microvilli. The purpose of both structures is to increase the small intestine’s surface area so that nutrient absorption is enhanced. Appendix • It doesn’t have any real function. But it can make people very painful. Appendix Large intense • The large intestine takes about 16 hours to finish the digestion of the food. It removes water and any remaining absorbable nutrients from the food before sending the indigestible matter to the rectum. The colon absorbs vitamins which are created by the colonic bacteria - such as vitamin K, vitamin B12, thiamine and riboflavin. It also compacts feces, and stores fecal matter in the rectum until it can be discharged the anus in defecation. BACK TO HOME Pelvic Cavity • Rectum • Anus • Alimentary Canal Rectum • The rectum intestinum acts as a temporary storage site for feces. As the rectal walls expand due to the materials filling it from within, stretch receptors from the nervous system located in the rectal walls stimulate the desire to defecate. If the urge is not acted upon, the material in the rectum is often returned to the colon where more water is absorbed from the feces. If defecation is delayed for a prolonged period, constipation and hardened feces results. Anus • The anus is an opening at the opposite end of an animal's digestive tract from the mouth. Its function is to control the expulsion of feces, unwanted semi-solid matter produced during digestion, which, depending on the type of animal, may include: matter which the animal cannot digest, such as bones; food material after all the nutrients have been extracted, for example cellulose; ingested matter which would be toxic if it remained in the digestive tract; and dead or excess gut bacteria like E.coli. Alimentary Canal • Imagine that you put one end of a hose in your mouth and kept threading it through until it came out of your butt. That's more or less what the alimentary canal is. You put food in one end of the tube and it's processed during its journey to the other end of the tube, where the waste material comes out. BACK TO HOME