Digestive System Flashcards
What are the main functions of the digestive system?
Ingestion, Propulsion, Digestion, Absorption, Defecation
What are the two main groups of organs in digestive system?
Alimentary canal (GI Tract) and Accessory digestive organs
Which groups of organs ingest, digest, absorb, and defecate?
the alimentary canal
What are the functions of the mouth?
mastication (chewing) food, tongue mixes masticated food with saliva, tongue initiates swallowing, taste buds on the tongue allow for taste
What are the layers of tissue in the alimentary canal?
Mucosa, submucosa, muscular externa, serosa
What layer of tissue contains nerve endings and blood vessels?
Submucosa
What layer of tissue contains fluid-producing cells?
Serosa
What is a sphincter?
a band of muscular tissue that can close and open to let things in
Food enters the stomach through what?
The cardioesophageal sphincter
Where does food empty into the small intestine?
Through the pyloric sphincter
What are rugae?
internal folds of the mucosa in the stomach, when the stomach is empty
What are the only items absorbed in the stomach?
aspirin and alcohol
What do chief cells do?
produce protein-digesting enzymes (pepsinogens)
What do parietal cells do?
produce hydrochloric acid that activates enzymes
What do mucous neck cells do?
produce thin acidic mucus
What do enteroendocrine cells do?
produce local hormones such as gastrin
What are the functions of the stomach?
Temporary storage tank for food, site of food breakdown, chemical breakdown of protein begins, delivers chyme (processed food) to the intestine
What is the main function of the small intestine?
Site of nutrient absorption into the blood
Subdivisions of small intestine
Duodenum, jejunum, Ileum
Functions of the large intestine
delivers indigestible food, resident bacteria digest remaining nutrients, vitamins ions and remaining water are absorbed
What does feces contain?
undigested food residues, mucus, bacteria, and water
Are digestive enzymes produced in the large intestine?
No
Subdivisions of the large intestine
cecum, appendix, colon, rectum, anal canal, anus
Subdivisions of the colon
Ascending, transverse, descending, sigmoid
External anal sphincter
formed by skeletal muscle meaning it is voluntary
internal anal canal
formed by smooth muscle and is involuntary
What are the salivary glands?
parotid, submandibular, sublingual
What is saliva?
mixture of mucus and serous fluids (watery solution with dissolved proteins)
What are the functions of saliva?
helps to moisten and bind food together into a bolus, contains salivary amylase, lysozymes and antibodies inhibit bacteria, and dissolves chemicals so they can be tasted
What is salivary amylase?
enzyme that breaks down starches
Main functions of the pancreas
produce insulin and glucagon
What is the largest gland in your body?
liver
What is the digestive role of the liver?
to produce bile (yellow-green watery solution)
what is the main purpose of bile?
break down fats
What is the main function of the gallbladder?
Stores bile for later secretion
what is propulsion?
movement of foods from one region of the digestive system to another
What is peristalsis?
alternating waves of contraction and relaxation that squeeze food along the GI tract
What is segmentation?
Movement of materials back and forth to foster mixing in the small intestine
