The Digestive System And Digestive Disorders Flashcards
(26 cards)
Alimentary Canal
mouth, pharynx, esophagus, stomach, small intestine, large intestine and anus and accessory organs of digestion
Function of the Digestive System
to convert food into simple nutrients for use by the cells of the body
Nutrients are: Vitamins Minerals Water Fats Proteins Carbohydrates
Mouth
Begins the process of breaking down food
Adds enzymes from saliva to start carbohydrate breakdown
Moistens food with saliva
Pharynx
Common passage for air and food
Gag reflex will keep food out of the trachea
Rhythmic contractions (peristalsis) push food into the esophagus
Esophagus
Continue peristalsis to move food particles to the stomach
Stomach
Muscular sac
Holds food up to 4 hours
Strong contractions churn and further break up food
Begin protein digestion
Gastric juices mix with food to produce a semi-liquid substance called chyme
Small Intestine: Composed of three parts
approximately 6 meters (20 ft) long
Duodenum: more digestive juices are added to the chyme
Jejunum: absorption of nutrients through villi lining the walls
nutrients are passed into the capillaries and transported to the cells
Ileum: final absorption of nutrients
remaining chyme is moved to the large intestine for absorption
Large Intestine: (colon)
final absorption of any remaining h2o and vitamins
solid waste matter passes to the rectum for elimination through the anus
Accessory Organs of Digestion
Tongue: manipulates food for thorough chewing by the teeth
propels food particles backwards to the pharynx for swallowing
Salivary glands: excretes enzymes for the chemical breakdown of food
moistens food for easier passage
Teeth: Cut, chop and grind food into smaller particles for ease of swallowing
Pancreas
Secretes enzymes that are the most important for the breakdown of food particles
***secretes insulin via the ‘Islets of Langerhans
Secretes insulin
Gall bladder
Stores bile
Liver
Metabolizes fats, protein and carbohydrates
Detoxifies substances from the blood
Stores fat-soluble vitamins
Excretes bile, cholesterol and bilirubin
The processes of digestion
Mechanical: food is broken down so it can be moved through the digestive tract by peristalsis
Begins with chewing with the teeth
Chemical: Enzymes combine with food to further the breakdown into simple nutrients that the body can utilize
Begins in the mouth with saliva
Vomiting
the act of expelling stomach contents through the mouth
signals illness or injury that can be life-threatening
Gastro-esophageal Reflux Disease (GERD)
Common disorder of unknown cause
Muscle band at the end of the esophagus relaxes at inappropriate times
Allowing stomach acids to back up into the esophagus
Gallbladder Disease
Pear-shaped sac that stores bile to aid in the digestion of fat
Components of bile form stones in the gallbladder which can cause inflammation
Stones can obstruct the opening of the gallbladder
Hepatitis (liver disease)
1) Hepatitis A:
spread by fecal-oral route (not washing hands)
vaccine exists
once you have had the virus you generally have immunity
2) Hepatitis B:
blood and body fluids
vaccine exists
no cure but if you recover from the disease you can have immunity
3) Hepatitis C: blood and body fluids no vaccine no cure responsible for most of the liver damage
Peristalsis
Is a series of wave-like muscle contractions that moves food to different processing stations in the digestive tract
Cirrhosis
Result of chronic liver disease
Liver tissue is gradually replaced with scar tissue which affects liver function
Most commonly caused by alcoholism and Hep C virus
No cure
Treatment can halt further liver damage
Celiac Disease
Small intestine disorder
Caused by a reaction to gluten protein found in wheat
Irritable Bowel Syndrome (IBS)
Bowel disorder characterized by abdominal pain and changes in bowel habits
Types of IBS
IBS with diarrhea: Abdominal bloating / abdominal pain / urgency / frequent loose watery stools that sometimes contain mucus
IBS with constipation: Abdominal bloating / severe abdominal pain / hard lumpy stools / need to strain to pass stools / feeling of incomplete bowel emptying
Colitis
Inflammation of the colon
Crohn’s Disease
Chronic inflammatory condition of the GI tract
Characterized by flare-ups and periods of remission
Most commonly affects the last part of the small intestine and the large intestine
