Nutrition Vocabulary Chapter 3

Front 1

digestion

Back 1

the process by which food is broken down into absorbable units

Front 2

absorption

Back 2

the uptake of nutrients by the cells of the small intestine for transport into either the blood or lymph

Front 3

gastrointestinal tract

Back 3

the digestive tract; the principal organs are th stomach and intestines

Front 4

lumen

Back 4

the space within a vessel, such as the intestine

Front 5

mouth

Back 5

the oral cavity containing the tounge and teeth

Front 6

pharynx

Back 6

the passageway leading from the nose and mouth to the larynx and esophagus, respectively

Front 7

epiglottis

Back 7

cartilage in the throat that guards the entrance to the trachea and prevents fluid or food from entering it when a person swallows

Front 8

esophagus

Back 8

the food pipe; the conduit from the mouth to the stomach

Front 9

sphincter

Back 9

a circular muscle surrounding, and able to close, a body opening. Sphincters are found at specific points along the GI tract and regulate the flow of food particles

Front 10

esophageal sphincter

Back 10

a sphincter muscle at the upper or lower end of the esophagus

Front 11

cardiac sphincter

Back 11

lower esophageal sphincter

Front 12

stomach

Back 12

a muscular, elastic, sac-like portion of the digestive tract that grinds and churns swallowed food, mixing it with acid and enzymes to form chyme

Front 13

pyloric sphincter/pylorus/pyloric valve

Back 13

the circular muscle that separates the stomach from the small intestine and regulates the flow of digested food into the small intestine

Front 14

small intestine

Back 14

10 foot length of small-diameter intestine that is the major site of digestion of food and absorption of nutrients. Its segments are the duodenum, jejunum, and ileum

Front 15

gallbladder

Back 15

the organ that stores and concentrates bile. When it receives a signal that fat is present in the duodenum, the gallbladder contracts and squirts bile through the bile duct into the duodenum

Front 16

pancreas

Back 16

a gland that secretes digestive enzymes and juices into the duodenum--also secretes hormones into the blood that help to maintain glucose homeostasis

Front 17

duodenum

Back 17

the top portion of the small intestine (about 1 foot long) responsible for the majority of chemical digestion in the small intestine

Front 18

jejunum

Back 18

the first 2/5 of the small intestine beyond the duodenum

Front 19

ileum

Back 19

the last segment of the small intestine

Front 20

ileocecal valve

Back 20

sphincter separating the small and large intestines

Front 21

large intestine/colon

Back 21

the lower portion of the intestine that completes the digestive process. Its segments are the ascending colon, the transverse colon, the descending colon, and the sigmoid colon

Front 22

appendix

Back 22

a narrow blind sac extending from the beginning of the colon that stores lymph cells

Front 23

rectum

Back 23

the muscle terminal part of the intestine, extending from the sigmoid colon to the anus

Front 24

anus

Back 24

the terminal outlet of the GI tract

Front 25

digestive system

Back 25

all the organs and glands associated with the ingestion and digestion of food

Front 26

bolus

Back 26

a portion, with respect to food, the amount swallowed at one time

Front 27

chyme

Back 27

the semi-liquid mass of partly digested food expelled by the stomach into the duodenum

Front 28

peristalsis

Back 28

wavelike muscular contractions of the GI tract that push its contents along

Front 29

segmentation

Back 29

a periodic squeezing or partitioning of the intestine at intervals along its length by its circular muscles

Front 30

reflux

Back 30

backward flow

Front 31

catalyst

Back 31

a compound that facilitates chemical reactions without itself being changed in the process

Front 32

pH

Back 32

the unit of measure expressing a substance's acidity or alkalinity

Front 33

stools/feces

Back 33

waste matter discharged from the colon

Front 34

emulsifier (bile)

Back 34

brings fats into suspension in water so enzymes can break them down into their component parts

Front 35

villi (villus=1)

Back 35

finger-like projections from the folds of the small intestine

Front 36

microvilli (microvillus=1)

Back 36

tiny, hairlike projections on each cell of every villus that can trap nutrient particles and transport them to the cells

Front 37

crypts

Back 37

tubular glands that lie between the intestinal villi and secrete intestinal juices into the small intestine

Front 38

goblet cells

Back 38

cells of the GI tract (and lungs) that secrete mucus

Front 39

aorta

Back 39

the large, primary artery that conducts blood from the heart to the body's smaller arteries

Front 40

arteries

Back 40

vessels that carry blood from the heart to the tissues

Front 41

capillaries

Back 41

small vessels that branch from an artery. Capillaries connect arteries to veins. Exchange of oxygen, nutrients, and waste materials takes place across capillary walls

Front 42

veins

Back 42

vessels that carry blood to the heart

Front 43

hepatic portal vein

Back 43

the vein that collects blood from the GI tract and conducts it to the capillaries in the liver

Front 44

hepatic vein <3

Back 44

the vein that collects blood from the liver capillaries and returns it to the heart

Front 45

lymphatic system

Back 45

a loosely organized system of vessels and ducts that convey fluids toward the heart. The GI part of the lymphatic system carries the products of fat digestion into the bloodstream

Front 46

lymph

Back 46

a clear yellowish fluid that is similar to blood except that it contains no red blood cells or platelets. Lymph from the GI tract transports fat and fat-soluble vitamins to the bloodstream via lymphatic vessels

Front 47

thoracic duct

Back 47

the main lymphatic vessel that collects lymph and drains into the left subclavian vein

Front 48

subclavian vein

Back 48

the vein that provides passageway from the lymphatic system to the vascular system

Front 49

yogurt

Back 49

milk product that results from the fermentation of lactic acid in milk by Lactobacillus bulgaricus and Streptococcus thermophilius

Front 50

probiotics

Back 50

living microorganisms found in foods that, when consumed in sufficient quantities, are beneficial to health

Front 51

homeostasis

Back 51

the maintenance of constant internal conditions (such as blood chemistry, temperature, and blood pressure) by the body's control systems. A homeostatic system is constantly reacting to external forces to maintain limits set by the body's needs.

Front 52

hormones

Back 52

chemical messengers. Hormones are secreted by a variety of glands in response to altered conditions in the body. Each hormone travels to one or more specific target tissues or organs, where it elicits a specific response to maintain homeostasis

Front 53

gastrin

Back 53

a hormone secreted by cells in the stomach wall.
Target organ; the gland of the stomach.
Response: secretion of gastric acid

Front 54

secretin

Back 54

a hormone produced by cells in the duodenum wall.
Target organ: the pancreas
Response: secretion of bicarbonate-rich pancreatic juice

Front 55

cholecystokinin (CCK)

Back 55

hormone produces by cells of the intestinal wall.
Target organ: the gallbladder
Response: release of bile and slowing of GI motility

Front 56

proenzyme/zymogen

Back 56

inactive precursor of an enzyme