Nutrition Chapter 4
Diverticulitis
Condition characterized by inflamed diverticula
Mechanical digestion
Refers to physical treatments that food undergoes while it is in the intestinal tract
Chemical Digestion
Refers to the breakdown of large nutrient molecules in food into smaller components, primarily by the action of enzymes
Hemorrhoids
Swollen veins in the anal cavity
Pepsin
active enzyme that begins the enzymatic digestion of proteins
Digestive Tract or Gastrointestinal Tract (GI tract)
alimentary canal or gut
Digestive system
body system that breaks down food into its components , absorbs nutrients, and eliminates the waste
Mucous cells
cells that secrete mucus
Hormones
chemical messengers secreted by organs of the endocrine system that convey information to target cells
Gastroesophageal reflux disease (GERD)
chronic condition characterized by frequent heartburn that can damage the esophagus
Gasstric juice
collection of stomach secretions that includes mucus, hydrochloric acid, intrinsic factor, and digestive enzymes
Anosmia
complete inability to dtect odors
Diverticulosis
condition characterized by the presence of diverticula
Inflammatory bowel disease (IBD
condition that is characterized by chronic inflammation of the GI tract
Hypogeusia
diminished ability to taste substances
Dumping syndrome
disorder that occurs when chyme flows too rapidly into the small intestine
Salivary amylase
enzyme in saliva that begins trarch digestioin
Lysozyme
enzyme in saliva that can destroy some bacteria that are in food or the mouth
Lingual lipase
enzyme secreted into saliva that begins fat digestion
Cecum
first segment of the large intestine
Duodenum
first segment of the small intestine
Epiglottis
flap of tough tissue that prevents the food from entering the larynx and trachea
Bile
fluid that is produced in the liver and stored in the gallbladder until it is needed for that digestion and absorption
Prebiotics
food components that beneficial bacteria in the large intestine use for fuel
lumen
hollow pass through which food and fluids can pass (digestive tract)
Secretin
hormone secreted by the duodenum and first part of the jejunum that stimulates the pancreas and liver to release a bicarbonate-rich solution into the small intestine
Cholecystokinin (CCK)
hormone secreted by the mucosa of the small intestine that stimulates the gallbladder to contract and the pancreas to release pancreatic juice into the small intestine
Gastrin
hormone that stimulates stomach motility and gastric gland secretions
Constipation
infrequent bowel movements and feces that are difficult to eliminate
Mucosa
innermost layer of the digestive tract wall
Goblet cells
intestinal cells that secrete mucus
Rectum
last section of the large intestine
Ileum
last segment of the small intestine
Probiotics
live microorganisms that promote good health for their human hosts
Bolus
mass of food that has been chewed, moistened, mixed with saliva, and swallowed
Jejunum
middle segment of the small intestine
Oral cavity
mouth
Stomach
muscular sac that stores and mixes food
Esophagus
muscular tube that extends about 10 inches from the pharynx to the upper portion of the stomach
Heartburn
pain generally felt in the upper chest that results from the passage of acidic contents from the stomach into the esophagus
Micorflora
population of several kinds of bacteria
Digestion
process of breaking down large food molecules into nutrients that the body can use
Absorption
process of removing nutrients from the intestinal tract and enabling them to enter the circulatory or lymphatic system
Enzyme
protein that speeds up the rate of a chemical reaction without being altered in the process
Ileocecal sphincter
region of ileum that controls the rate of emptying undigested material into the large intestine
Lower esophageal sphincter (LES)
region of the lower part of the esophagus that controls flow of material into the upper part of the stomach; also known as the gastroesophageal sphincter
Pyloric sphincter
region of the stomach that regulates the flow of chyme into the small intestine
Upper esophageal sphincter (UES)
region of the upper part of the esophagus that opens to allow a mass of food to enter the esophagus
Segmentation
regular contractions of circular intestinal muscles followed by muscular relaxations that mix chyme within a short portion of the small intestine
Pharanx
section of the alimentary canal that connects the nasal cavity with the tope of the esophagus
chyme
semiliquid mass that forms when food mixes with gastric juice
Alkaline
solutions with pH values higher than 7
Acidic
solutions with pH values lower than 7
G cells
stomach cells that secrete gastrin
Parietal cells
stomach cells that secrete intrinsic factor and the components of hydrochloric acid into the lumen of the stomach
Chief cells
stomach cells that secrete some chemically inactive digestive enzymes
Salivary glands
structures that produce saliva and secret the fluid into the oral cavity
Intrinsic factor
substance necessary for absorbing vitamin B-12
Sphincters
thinckened regions of circular muscle that control the flow of contents at various points in the GI tract
Diverticula
tiny pouches that form in the wall of the colon
Ageusia
total loss of the ability to taste substances
Ulcerative colitis (UC)
type of IBD that causes ulcers to form in the mucosa of the colon and rectum
Crohns disease
type of IBD; the body's immune system cells attack normal intestinal cells, damaging parts of the intestines
Hepatic portal vein
vein that transports absorbed nutrients to the liver
Lacteal
vessel of the lymphatic system
Mucus
water slippery fluid secreted by special cells
Saliva
watery fluid that contains mucus and a few enzymes