Digestive+System

Chapter 8 Digestive System 8.1 Overview of Digestion

1. Describe in you words the processes that occur in the digestive system (ingestion, digestion, movement, absorption, elimination) indisgestion--> the mouth takes in food digestion--> when the food is divided into smaller pieces (mechanical) (chemical food beins to dissolve.. can start in the mouth when you salvate. it is also happeing in your stomache  when         your stomache acids break down the food into a sloshy mixture.

Movement--> food is passed from one organ to the next.. the indigestible remains leave must be expelled. Absorption--> molecules produced by the G.I. tract cross the wall of the GI tract and enter te cells lining the tract. Elimination--> after all the nutrients and water is sucked out of the remains.. the reains leave the body through the anus.

8.2 First Part of the Digestive Tract

1. Describe the MECHANICAL and CHEMICAL digestion that occurs in the mouth. Mechanical-->(your teeth) your mouth condenses the food up into smaller peices.. The mouth salvates and gets the food into a substances that can pass through the digestive system. (sugar is the only food that the mouth can totally get down to the apporpriate size)--> it just dissolves in your mouth. Chemical--> chemical digestions can start in the mouth But, is not completed until it reaches the stomache..

the salviory glands are important in both processes.

2. What is heartburn? when some of the stomache's acid contents escape into the esophagus

3. What is a dental cavity? (What causes it?) when bacteria within the mouth metabolize sugar and give off acids, wich erode teeth.

8.3 Stomach and Small Intestine 1. What are the functions of the stomach and how is the wall of the stomach modified to perform these functions? the stomache stores food, initiates the digestion of protein and contrrols the movement of chyme into the small intestine. the wall of the stomache has 4 layers.. but two are modified particular functions. (muscularis)--> contains three layers off smooth muscle. it also contains another layer of smooth muscles that ru oblique to the other two. this allows the stomache to stretch and to mechanically break down food into small fragments.

2. What are the functions of the small intestine and how is the wall of the small intestine modified to perform these functions? teh small intestine contains enzymes to digest all types of foods, prmarily carbs, proteins and fats. the pancreatic juices have sodium bicarbonate which muetralizes chyme.

3. What is lactose intolerance? What causes it and what are the symptoms? people who do not have the brush border enzyme called lactose cannot digest lactose. they suffer from diahrrea, gas, bloating, and abdominal cramps sfter drinking milk or eating dairy products.

8.4 Three accessory organs. 1. What are the three main accessory organs and how do they assist the digestive process? pancreas--> it secreates important digestive fluids. gallbladder--> bile is stored in the galbladder until it is sent via bile ducts.

2. What is a gallstone? when liquids in the galbladder hardens and creates stones.

3. What is hepatitis? inflamation of the liver 4. What is cirrhosis? the organ becomes fatty ad then liver tissue is replaced y inactive flibrous scar tissue. 8.5 Large Intestine 1. What is the function of the large intestine? cecum colonrectum and the anal canal. the alrge intestine is larger in diameter 2. Briefly describe the disorders of the large intestine: diarrhea, constipation, diverticulosis, hemorrhoids, IBS, IBD, polyps, cancer.

diarrhea--> the small and large intestine is not able to remove the liquid.. constipaion--> a back up within the large intestine.. the fece are dry and hard.. water and fiber will restore you to regular digestion. hemroids--> large inflamed blood vessels at the aus.

Diverticuosis--> spots of mucous in the large intestine

irritable bowel syndrome--> the muscle contracts frequently without ay sort of pattern..

IBD--.> a number of inflamatory diorders, ulcers.. ect.