Chapter 23 Flashcards
Digestive System
Define: peristalsis
Adjacent segments of involuntary waves of contraction and relaxation in the organ wall
Define: segmentation
Nonadjacent segments that allow for food mixing and effective nutrient absorption
List and describe the six GI tract activities
- ingestion: eating
- propulsion: swallowing and peristalsis
- mechanical breakdown: chewing and segmentation
- digestion: food breakdown using enzymes
- absorption: nutrients travels from lumen to blood/lymph
- defecation: waste removal through the anus
Double layer of peritoneum that is fused together, holding organs in place, providing routes for vessels, lymphatics, and nerves
mesentery
A piercing abdominal wound, perforating ulcer, or a ruptured appendix can cause what disease?
Pertonitis
Describe the basic functions of the GI tract and the accessory organs
GI tract: mouth, pharynx, esophagus, stomach, and intestines
- function: muscular tube from mouth to anus that breaks down and absorbs nutrients
Accessory organs: teeth, tongue, gallbladder, salivary glands, liver, and pancreas
- function: produces secretions and other means to break down food
Describe the difference between short and long reflexes of the enteric nervous system
Short: responds to stimuli from the GI tract, mediated by the gut brain, and responsible for stomach growl
Long: responds to signals from CNS, parasympathetic enhances digestion, sympathetic inhibits digestion
____ cells of the salivary glands contains enzymes like ____ that breakdown starch
serous; amylase
The ____ ____ is produced by the stomach to allow for B12 absorption
intrinsic factor
What are the digestive functions of the oral cavity
- moisten food then compact into bolus
- breakdown of food w/ amylase enzymes and lipase
- dissolves food chemicals for taste
Compare the functions of cell types in the stomach mucosa
- simple columnar epithelium = secretes mucus
- loose areolar connective tissues = absorbs nutrients
- smooth muscle cells = local movement, enhances absorption and secretion
Identify what causes GERD and what it stands for
Gastroesophageal reflux disease is caused by heartburn and hiatal hernia
Peptic / ____ ulcers are caused by bacterium ____ ____ and by ____-____ drugs
gastric; Helicobacter pylori; anti-inflammatory
TRUE OR FALSE:
Colon cancer often does not have symptoms but can be caught early and treated
True
____ is caused by viral infection, drug toxicity, and wild mushroom poisoning. In progressive cases this can lead to ____, which is also caused by alcoholism
Hepatitis; cirrhosis
Biliary culculi AKA ____ is caused by too much ____ OR too few bile ____
gallstones; cholesterol; salts
Inflamed diverticula that may rupture and leak into the peritoneal cavity.
Diverticulitis
The diverticula is defined as ____ of mucosa
herniations
What is the function of hepatocytes?
- Bile production
- Stores fat-soluble vitamins
- Removes toxins through urea
- Makes plasma proteins and stores glycogen
How does the duodenum interact with the pancreas and gallbladder products?
The bile duct and main pancreatic duct converge in the wall of the duodenum to form the hepatopancreatic ampulla which continues into the duodenum
Compare and contrast the small and large intestines
Small: major digestive organ, 3 parts (duodenum, jejunum, and ileum), has brush border enzymes, and intestinal crypts
Large: stores residue, absorbs water, 5 parts (cecum, appendix, colon, rectum, and anal canal), thicker mucosa
What are the actions of cholecystokinin (CCK) and secretin
CCK: inhibits stomach secretions, increases pancreatic juices, relaxes sphincter to admit bile and pancreatic juices into the duodenum, stimulates bile expulsion in gallbladder
Secretin: inhibits gastric gland and gastric motility, increases bile output in liver, increases pancreatic juice output rich in bicarbonate ions
Histamine is found in the stomach mucosa and activates the release of ____ ____ in ____ cells
hydrochloric acid; parietal
