Ch 2: Food Intake, Digestion & Absorption Flashcards
Soluble
Disposed to being dissolved.
General Circulation
The flow of blood throughout the entire body.
Monounsaturated Fat
Fatty acid containing one double or triple bond between carbons.
Triglyceride
Compound with three molecules of fatty acids bound with one molecule of glycerol; the storage form of fat in humans.
Oxidation
Increase of positive charges on an atom or the loss of negative charges; the opposite reaction is reduction.
Gastrointestinal (GI) Tract
The long tube through the body composed of stomach and intestines.
Calorie
Amount of energy required to raise the temperature of one kilogram of water by 1 degree Celsius; equal to 4184 joules.
Organic Molecules
Relating to or containing carbon compounds.
Adenosine Diphosphate (ADP)
Nucleotide produced in living cells; made up of adenosine and two phosphate groups. reversibly renewed to ATP for energy transfer.
Mastication
To grind, crush, and chew food.
Bolus
A formed mass of soft, partially chewed food.
Bile
Fluid produced by the liver and stored in the gallbladder, ultimately secreted into the small intestine to alkalinize and emulsify foodstuffs.
Enterocyte
Absorptive cell of the intestine.
Villi
Small projections covering the surface of the mucous membrane lining the small intestine, through which nutrients and fluids are absorbed.
Amylase
Of pancreatic and salivary origin, this enzyme catalyzes the hydrolysis (splitting) of starch into smaller compounds.
Lipase
Catalyzes the splitting of fats into glycerol and fatty acids.
Pharynx
Throat
Epiglottis
Lid-like cartilaginous structure suspended over the entrance of the larynx; swallowing closes the opening to the trachea by placing the larynx against the epiglottis.
Lower Esophageal Sphincter
Also known as the cardia sphincter, a thick, muscular ring surrounding the opening between the esophagus and stomach.
Gastroesophageal Reflux
Condition in which acidic stomach contents flow back up into the esophagus.
Peristalsis
Waves of involuntary muscle contraction moving the contents of the GI tract forward.
Chyme
Partly digested food formed as a semi-fluid mass.
Pyloric Sphincter
Thick, muscular ring of mucous membrane surrounding the opening between the stomach and the duodenum.
Hiatal Hernia
Protrusion of the stomach through the esophageal hiatus of the diaphragm.
Hydrochloric Acid
Solution of hydrogen chloride in water; found in gastric juice.
pH
Measure of acidity and alkalinity; lower numbers are more acid, higher numbers are more alkaline; 7 is neutral.
Ileocecal Valve
Two folds of mucous membranes that form a valve between the large intestine (cecum) and the small intestine (ileum).
Pancreas
Large gland behind the stomach that secretes digestive enzymes and the hormones insulin and glucagon.
Bicarbonate
Organic salt (HCO3) that can neutralize acids.
Proteolytic Enzyme
Enzyme that hydrolyzes (breaks down) protein or peptides.
Gallbladder
Muscular sac where bile is stored.
Emulsification
To disperse, convert and suspend one liquid as droplets into another.
Enterohepatic Circulation
Circulation of substances such as bile salts between the intestine and the liver.
Feces
Waste discharged from the body through the anus.
Short Chain Fatty Acid
Fatty acid with fewer than eight carbons that is taken up directly through the portal vein, and produced while fiber is fermenting in the colon.
Carcinogens
Cancer-causing substances.
Prebiotic
Compound that is not digested but rather fermented by microflora and stimulates growth of healthy bacteria in the GI tract.
Probiotics
Live microorganisms that help to restore beneficial baxter in the GI tract.
Hepatic Portal System
Veins that carry blood from the capillaries of the stomach, intestine, pancreas, and spleen to the liver.
Exocrine
Secretion, such as saliva or bile, released outside its source by a duct.
Endocrine
Secretion, such as a hormone, distributed in the body by the bloodstream.
Glucoregulatory Hormone
Hormone that glances blood glucose levels, such as glucagon or insulin.
Neurotransmitter
Substances that transmits nerve impulses across a synapse.
Enteric Nervous System
The brain in the gut. A subdivision of the autonomic nervous system that controls the gastrointestinal organs.
Neuromuscular Junction
Junction of an efferent nerve fiber and the muscle fiber cell membrane.
Parasympathetic Nervous System
Part of the autonomic nervous system that controls secretions and the tone of smooth muscle, along with cardia muscle activity.
Vasodilation
Widening of blood vessels.
Microvilli
Microscopic hair structures that increase the surface area of cells; many are found in the GI tract.
Intestinal Brush Border
All of the villi that form a brush-like border inside the intestine.
Simple Diffusion
Spontaneous movement of particles from an area of high concentration to an area of low concentration.
Facilitated Diffusion
Transport that requires a carrier molecule; occurs when diffusion of a substance on its own is not possible.
Active Transport
Movement of particles from an area of low concentration to an area of high concentration; requires energy and enzymes.
Concentration Gradient
Difference in the concentration of volutes in a solution between two areas.
Peptic Ulcer
Found on the wall of the duodenum or stomach, this ulcer results when gastric juices and H. pylori combine.
Emesis
Vomiting
Inflammatory Bowel Disease
Inflammation-based disorder of the intestinal tract, such as Crohn’s disease or ulcerative colitis.
Food Intolerance
Adverse reaction induced by food.
Glycogen
Chief sources of stored glucose in selected tissues.
Hepatocyte
Liver cell.
Deamination
Removal of an amine group from a compound.
Lipoprotein
A class of proteins with hydrophobic core of triglycerides or cholesterol surrounded by hydrophilic phospholipids, aplolipoproteins and cholesterol.
First Pass Metabolism
When a substance is swallowed and absorbed, it first travels through the hepatic portal system for metabolism by the liver; this “first pass” can reduce the availability of the substance to the body.
Systemic Circulation
When blood travels from the heart to the arteries and capillaries, exchanging oxygen for carbon dioxide and returning via the veins to the heart for pulmonary circulation.
Transamination
The transfer of an amino group from an amino acid to alpha-keto acid.
Acetyl-CoA
Co-enzyme that plays a role in intermediary metabolism; can enter the Krebs cycle to produce energy and be used for fatty acid synthesis.
Keton Body
Either acetoacetic acid, acetone, or beta-hydroxylbutyric acid with a carbonyl group attached to two carbon atoms.
