Gastrointestinal System

What are the four main functions of the GI system?

1. motility

2. digestion

3. absorption

4. elimination

absorption

transport of digested end products from the lumen of the GI tract to the blood or lymph

What is the main function of the alimentary canal?

nourish the body

What is the main function of the accessory digestive organs?

orchestrating the breakdown of food and assimilating its nutrients into the body

What two main group can the organs of the digestive system be separated into?

the accessory digestive organs and the alimentary canal

esophagus

is 10 inches long and runs from the pharynx, to the diaphragm, and down to the stomach

large intestine

much larger in diameter than the small intestine, but is about 5 inches long and extends from the ileocecal valve to the anus

What is the function of the large intestine?

to dry out indigestible food by absorbing water

What is included in the accessory digestive system?

teeth, salivary glands, pancreas, liver, and gallbladder

pancreas

a gland that extends across the abdomen and produces insulin, glucagon, and enzymes that breaks down all categories of food

liver

largest gland in the body that has four lobes and is located under the diaphragm on the right side of the body

What is the digestive function of the liver?

to produce bile

bile

a yellow to green watery solution that further emulsifies fat globules through bile salts

gallbladder

small green sac in the shallow groove of the inferior liver

What are the six steps of digestion?

1. cephalic (chewing)

2. swallowing (deglutition)

3. stomach digestion

4. small intestine digestion

5. absorption

6. waste elimination

What part of food stimulates the parasympathetic nervous system to increase the secretion of gastric juice?

the sight, smell, and taste

gastrin

a hormone that stimulates the stomach glands to produce more pepsinogen, mucus, and hydrochloric acid

peristalsis

the movement of food through the digestive tract