Digestive system lab quiz review PDF

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Digestive system lab quiz review...

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Lab Quiz 1 Review Digestive system: Structures of the gastrointestinal tract: ● ● ● ● ● ● ● ●

Mouth Pharynx Esophagus Stomach Small intestine Large intestine Rectum Anus

What are the structures that make up the mouth? ● ● ● ●

Incisors- chisel-shaped and adapted for cutting into food Cuspids (canine)- tear food Bicuspids (premolars)- crush and grind food Molars- grind food

Papillae are projections of the lamina propria there are 3 types: o Filiform papillae- have no taste buds but create friction to move the food around your mouth o Fungiform papillae- these taste buds resemble mushrooms and are scattered all over the o Circumvallate papillae- these taste buds form an inverted “V” on the posterior portion of the tongue. What part of the tongue senses taste? The anterior 2/3 of the tongue senses sweet, sour, and salty tastes. The posterior 1/3 of the tongue senses bitter tastes. What is Saliva? Saliva contains water, mucin, and salivary amylase. The pH of saliva is 6.35 to 6.85. There are 3 glands that secrete saliva into the mouth: o Parotid gland o Submandible gland o Sublingual gland What is the Pharynx and Where is it located? The Pharynx is the throat and has 3 regions: ● Nasopharynx- is located posterior to the nasal cavity ● Oropharynx- is located posterior to the oral cavity ● Laryngopharynx- is located posterior to the larynx and connects the mouth to the esaphogas.

What is the esophagus? The esophagus is the collapsible muscular tube that connects the pharynx to the stomach.

What is the stomach, where is it located, and What is its Function? ● The stomach is located in the right upper quadrant of the abdominopelvic cavity. ● The stomach mixes ingested food, saliva, and gastric juices (secretions) to form chyme ● Also holds food until the small intestine is ready to accept this food. What is gastric juice made up of? Gastric juice consists of hydrochloric acid, intrinsic factor, gastric lipase, and pepsinogen. Which stomach cells secrete gastric juice? (Surface mucous cells and mucous neck cells, Parietal cells, and Chief cells) 1) Surface mucous cells and mucous neck cells secrete mucus, which acts as a protective barrier that prevents damage to the stomach. 2) Parietal Cells secrete: ● Hydrochloric acid, which kills the most microorganisms and denatures proteins. ● Intrinsic factor, which is needed to absorb vitamin B12 (vitamin B12 needed to make RBC’s) 3) Chief cells secrete: ● Gastric lipase, which breaks down fats ● Pepsinogen, which is converted to pepsin (the active form) when it makes contact with the hydrochloric acid. Pepsin breaks down protein. What is the small intestine? The small intestine is a muscular tube that extends from the stomach to the cecum of the large intestine. Most of the digested food is absorbed into the blood through the small intestine. The small intestine has 3 sections: ● 1) Doudenum ● 2) Jejunum ● 3) Ileum What is the large intestine? The large intestine extends from the small intestine to the anus. The large intestine is also called the large bowel or colon and consists of 5 sections: ● Cecum- (attached to the ileum of the small intestine) ● Appendix- (vermiform appendix) serves no purpose in humans

● Ascending colon- (travels superiorly to the transverse colon) ● Transverse colon- (travels transversely across the abdomen to hook up with the descending colon) ● Descending colon- (travels inferiorly to the sigmoid colon) ● Sigmoid colon- (S-shaped structure connected to the rectum) (rectum stores feces), (feces empty along the anal canal and exit the body through a muscular opening called the anus) What is the function of the large intestine? ● The large intestine functions in the absorption of water, ions, and vitamins and the formation of feces. (Water, inorganic salts, epithelial cells, undigested food (such as fiber), and bacteria are expelled from the body as feces) What are the Accessory Structures of the Gastrointestinal Tract? ● The accessory structures of the gastrointestinal tract include liver, gallbladder, and pancreas. What is the liver and What is it located? ● The liver is composed of a right and a left lobe and is located in the right upper quadrant of the abdominopelvic cavity. ● The lobes of the liver are connected to each other and to the common bile duct (coming off the gallbladder) by the common hepatic duct What is the Function of the Liver? ● The liver functions in the metabolism of carbohydrates, lipids, and proteins, processes hormones and drugs, stores vitamins and excretes bilirubin. What is the gallbladder? The gall bladder lies between the lobes of the liver in the right upper quadrant. ● What is the function of the gallbladder? The gallbladder stores bile, under the influence of the hormones, cholecystokinin, the gallbladder contracts, ejecting bile through the cystic duct into the common bile duct and into the duodenum of the small intestine, where it emulsifies fats. ● What are Gallstones? Gallstones are made up of solidified bile salts, phospholipids, and cholesterol. ● What is the pancreas? The pancreas is located posterior to the stomach and is both and endocrine gland and an exocrine gland. About 99% of pancreatic cells are acini cells and function in exocrine secretion of pancreatic digestion. The other 1 percent and endocrine cells and are called the islets of Langerhans.

What do the acini cells secrete? The acini cells secrete: ● Pancreatic lipase: Pancreatic lipase breaks down fats (triglycerides) ● Pancreatic amylase: Pancreatic amylase breaks down starches (polysaccharides) ● Pancreatic nucleases: Pancreatic nucleases include ribonuclease and deoxyribonuclease, which break down nucleic acids. ● Trypsinogen: Trypsinogen is converted to its active form trypsin (in the intestines by enterokinase), which breaks down protein....