Ch.+8.3-8.5+Questions+SLS

**stomach **: Thick walled, j-shaped organ that lies on the left side of the body beneath the diaphragm. The stomach stores food, initiates the digestion process, and controls the movement of the chyme into the small intestine. **Rugae **: The mucosa of the stomach has deep folds called rugae, which disappear into the stomach as it fills to 1 L. **gastric glands **: Produce gastric juice. Which is an enzyme called Pepsin. **Pepsin **: Juice secreted by the gastric glands, which is an enzyme **small intestine **: The small intestine is the smaller of the two intestines which aid the digestive process. **Duodenum **: The first 25 cm of the small intestine. **Bile **: Bile emulsifies fat, and emulsification causes fat to disperse in water. **Lipase **: When the fat is broken down by bile, it is hydrolyzed to glycerol and fatty acids by lipase. **Villus **: The small intestine have finger like projections called villus which give the intestinal wall a soft, velvety appearance. **Lacteal **: A villus contains blood capillaries and a small lymphatic capillary, called a lacteal. **lactose intolerance **: People who do not have the enzyme lactase to break down the lactose suffer from Lactose Intolerance. **(1) What are the functions of the stomach? ** The functions of the stomach is to store food, initiate the digestion process and digest protein, as well as control the movement of the chyme into the small intestine.
 * 8.3 Stomach to Small Intestine **

**(2) What are the structures of the stomach that perform these functions and describe their role ** The stomach wall has four layers and two are modified for a particular function. The muscularis and the oblique layer mechanically break down food. The gastric glands secrete pepsin which digest protein and hydrochloric acid and mucus, which break down the proteins even further and activate the pepsin.

**(3) What are the functions of the small intestine? ** The functions of the small intestine is to secrete enzymes which break down proteins and carbohydrates necessary for digestion. Nutrients are also absorbed in the small intestine, which is beneficial to the body: sugars, fatty acids and amino acids.

**(4) What are the structures of the small intestine that perform these functions and describe their role? ** The duodenum, which is the first 25 cm of the small intestine, secrete enzymes to break down and emulsify the fat (bile.) Then lipase is secreted which breaks down the food even further, and lastly the wall of the small intestine uses villus to absorb nutrients which tend to be beneficial to the body, as well as help the digestive tract.

**8.4 Three Accessory Organs and Regulation of Secretions ** **pancreas **: Fish-shaped, spongy, grayish pink organ that is across the back of the abdomen behind the stomach. **pancreatic amylase **: Digests starch. **Trypsin **: digests protein. **Lipase **: digests fat. **Hormone **: a substance produced by one set of cells that affects a different set of cells, the so-called ‘target cells’. **Liver **: Largest and major metabolic gland in the body, lies mainly in the upper-right section of the abdominal cavity. **Bile: ** Helps the liver regulate the plasma proteins, as well as the quantity of cholesterol in the blood. **Bladder: ** Urine is collected here until excretion.

**(5) What are the three main accessory organs that assist with the digestive process? ** **Describe how each contributes to the digestion of food. ** The three main accessory organs that assist with the digestive process are The pancreas, the liver and the gall bladder. The pancreas further breaks down proteins, carbohydrates and fats, which the liver regulates the plasma proteins and cholesterol level in the blood stream. Lastly, the gall bladder stores the bile which is necessary in the liver.

**(6) How are digestive secretions regulated in the body? ** The nervous system and digestive hormones regulate the secretion of digestive juices into the body.

**8.5 The Large Intestine and Defecation ** **large intestine: ** The large intestine contains the cecum, the colon, the rectum and the anal canal. **Cecum: ** Lies below the junction with the small intestine, is the blind end of the large intestine. **vermiform appendix: ** A small projection in the cecum, which plays a role in fighting infections. **colon **: Goes up the right side of the body to the liver; expulsion of feces.

**(7) What are the different parts of the large intestine? ** The different parts of the large intestine include the cecum, the vermiform appendix, and the colon.

**(8) What is the function of the large intestine? ** The function of the large intestine is to absorb water to prevent the body from dehydration. The large intestine also absorbs vitamins that are produced by bacteria called the intestinal flora. Lastly, the large intestine forms feces, or waste from food that the body doesn’t need.